diff --git a/sbp/Cargo.toml b/sbp/Cargo.toml
index a84bb47..6c3bc23 100644
--- a/sbp/Cargo.toml
+++ b/sbp/Cargo.toml
@@ -14,6 +14,8 @@ json = "0.12.1"
 # Internal feature flag to gate the expensive tests
 # which should be run only in release builds
 expensive_tests = []
+# Use f32 as precision, default is f64
+f32 = []
 
 [dev-dependencies]
 criterion = "0.3.0"
diff --git a/sbp/benches/maxwell.rs b/sbp/benches/maxwell.rs
index 5521cc3..f532e5e 100644
--- a/sbp/benches/maxwell.rs
+++ b/sbp/benches/maxwell.rs
@@ -1,6 +1,7 @@
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 use sbp::maxwell::System;
 use sbp::operators::{SbpOperator, Upwind4, UpwindOperator, SBP4};
+use sbp::Float;
 
 fn advance_system<SBP: SbpOperator>(universe: &mut System<SBP>, n: usize) {
     for _ in 0..n {
@@ -20,8 +21,8 @@ fn performance_benchmark(c: &mut Criterion) {
 
     let w = 40;
     let h = 26;
-    let x = ndarray::Array2::from_shape_fn((h, w), |(_, i)| i as f32 / (w - 1) as f32);
-    let y = ndarray::Array2::from_shape_fn((h, w), |(j, _)| j as f32 / (h - 1) as f32);
+    let x = ndarray::Array2::from_shape_fn((h, w), |(_, i)| i as Float / (w - 1) as Float);
+    let y = ndarray::Array2::from_shape_fn((h, w), |(j, _)| j as Float / (h - 1) as Float);
 
     let mut universe = System::<Upwind4>::new(x.clone(), y.clone());
     group.bench_function("advance", |b| {
diff --git a/sbp/src/euler.rs b/sbp/src/euler.rs
index a9d2512..1181597 100644
--- a/sbp/src/euler.rs
+++ b/sbp/src/euler.rs
@@ -1,10 +1,11 @@
 use super::grid::Grid;
 use super::integrate;
 use super::operators::{SbpOperator, UpwindOperator};
+use super::Float;
 use ndarray::azip;
 use ndarray::prelude::*;
 
-pub const GAMMA: f32 = 1.4;
+pub const GAMMA: Float = 1.4;
 
 // A collection of buffers that allows one to efficiently
 // move to the next state
@@ -16,7 +17,7 @@ pub struct System<SBP: SbpOperator> {
 }
 
 impl<SBP: SbpOperator> System<SBP> {
-    pub fn new(x: ndarray::Array2<f32>, y: ndarray::Array2<f32>) -> Self {
+    pub fn new(x: ndarray::Array2<Float>, y: ndarray::Array2<Float>) -> Self {
         let grid = Grid::new(x, y).expect(
             "Could not create grid. Different number of elements compared to width*height?",
         );
@@ -29,7 +30,7 @@ impl<SBP: SbpOperator> System<SBP> {
         }
     }
 
-    pub fn advance(&mut self, dt: f32) {
+    pub fn advance(&mut self, dt: Float) {
         let rhs_trad = |k: &mut Field, y: &Field, grid: &_, wb: &mut _| {
             let boundaries = BoundaryTerms {
                 north: y.south(),
@@ -51,14 +52,14 @@ impl<SBP: SbpOperator> System<SBP> {
         std::mem::swap(&mut self.sys.0, &mut self.sys.1);
     }
 
-    pub fn vortex(&mut self, t: f32, vortex_parameters: VortexParameters) {
+    pub fn vortex(&mut self, t: Float, vortex_parameters: VortexParameters) {
         self.sys
             .0
             .vortex(self.grid.x.view(), self.grid.y.view(), t, vortex_parameters);
     }
 
     #[allow(clippy::many_single_char_names)]
-    pub fn init_with_vortex(&mut self, x0: f32, y0: f32) {
+    pub fn init_with_vortex(&mut self, x0: Float, y0: Float) {
         // Should parametrise such that we have radius, drop in pressure at center, etc
         let vortex_parameters = VortexParameters {
             x0,
@@ -80,16 +81,16 @@ impl<SBP: SbpOperator> System<SBP> {
         &self.sys.0
     }
 
-    pub fn x(&self) -> ArrayView2<f32> {
+    pub fn x(&self) -> ArrayView2<Float> {
         self.grid.x.view()
     }
-    pub fn y(&self) -> ArrayView2<f32> {
+    pub fn y(&self) -> ArrayView2<Float> {
         self.grid.y.view()
     }
 }
 
 impl<UO: UpwindOperator> System<UO> {
-    pub fn advance_upwind(&mut self, dt: f32) {
+    pub fn advance_upwind(&mut self, dt: Float) {
         let rhs_upwind = |k: &mut Field, y: &Field, grid: &_, wb: &mut _| {
             let boundaries = BoundaryTerms {
                 north: y.south(),
@@ -114,10 +115,10 @@ impl<UO: UpwindOperator> System<UO> {
 
 #[derive(Clone, Debug)]
 /// A 4 x ny x nx array
-pub struct Field(pub(crate) Array3<f32>);
+pub struct Field(pub(crate) Array3<Float>);
 
 impl std::ops::Deref for Field {
-    type Target = Array3<f32>;
+    type Target = Array3<Float>;
     fn deref(&self) -> &Self::Target {
         &self.0
     }
@@ -143,29 +144,29 @@ impl Field {
         self.0.shape()[1]
     }
 
-    pub fn rho(&self) -> ArrayView2<f32> {
+    pub fn rho(&self) -> ArrayView2<Float> {
         self.slice(s![0, .., ..])
     }
-    pub fn rhou(&self) -> ArrayView2<f32> {
+    pub fn rhou(&self) -> ArrayView2<Float> {
         self.slice(s![1, .., ..])
     }
-    pub fn rhov(&self) -> ArrayView2<f32> {
+    pub fn rhov(&self) -> ArrayView2<Float> {
         self.slice(s![2, .., ..])
     }
-    pub fn e(&self) -> ArrayView2<f32> {
+    pub fn e(&self) -> ArrayView2<Float> {
         self.slice(s![3, .., ..])
     }
 
-    pub fn rho_mut(&mut self) -> ArrayViewMut2<f32> {
+    pub fn rho_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![0, .., ..])
     }
-    pub fn rhou_mut(&mut self) -> ArrayViewMut2<f32> {
+    pub fn rhou_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![1, .., ..])
     }
-    pub fn rhov_mut(&mut self) -> ArrayViewMut2<f32> {
+    pub fn rhov_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![2, .., ..])
     }
-    pub fn e_mut(&mut self) -> ArrayViewMut2<f32> {
+    pub fn e_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![3, .., ..])
     }
 
@@ -173,10 +174,10 @@ impl Field {
     pub fn components(
         &self,
     ) -> (
-        ArrayView2<f32>,
-        ArrayView2<f32>,
-        ArrayView2<f32>,
-        ArrayView2<f32>,
+        ArrayView2<Float>,
+        ArrayView2<Float>,
+        ArrayView2<Float>,
+        ArrayView2<Float>,
     ) {
         (self.rho(), self.rhou(), self.rhov(), self.e())
     }
@@ -184,10 +185,10 @@ impl Field {
     pub fn components_mut(
         &mut self,
     ) -> (
-        ArrayViewMut2<f32>,
-        ArrayViewMut2<f32>,
-        ArrayViewMut2<f32>,
-        ArrayViewMut2<f32>,
+        ArrayViewMut2<Float>,
+        ArrayViewMut2<Float>,
+        ArrayViewMut2<Float>,
+        ArrayViewMut2<Float>,
     ) {
         let mut iter = self.0.outer_iter_mut();
 
@@ -200,38 +201,38 @@ impl Field {
         (rho, rhou, rhov, e)
     }
 
-    fn north(&self) -> ArrayView2<f32> {
+    fn north(&self) -> ArrayView2<Float> {
         self.slice(s![.., self.ny() - 1, ..])
     }
-    fn south(&self) -> ArrayView2<f32> {
+    fn south(&self) -> ArrayView2<Float> {
         self.slice(s![.., 0, ..])
     }
-    fn east(&self) -> ArrayView2<f32> {
+    fn east(&self) -> ArrayView2<Float> {
         self.slice(s![.., .., self.nx() - 1])
     }
-    fn west(&self) -> ArrayView2<f32> {
+    fn west(&self) -> ArrayView2<Float> {
         self.slice(s![.., .., 0])
     }
-    fn north_mut(&mut self) -> ArrayViewMut2<f32> {
+    fn north_mut(&mut self) -> ArrayViewMut2<Float> {
         let ny = self.ny();
         self.slice_mut(s![.., ny - 1, ..])
     }
-    fn south_mut(&mut self) -> ArrayViewMut2<f32> {
+    fn south_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![.., 0, ..])
     }
-    fn east_mut(&mut self) -> ArrayViewMut2<f32> {
+    fn east_mut(&mut self) -> ArrayViewMut2<Float> {
         let nx = self.nx();
         self.slice_mut(s![.., .., nx - 1])
     }
-    fn west_mut(&mut self) -> ArrayViewMut2<f32> {
+    fn west_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![.., .., 0])
     }
 
     pub fn vortex(
         &mut self,
-        x: ArrayView2<f32>,
-        y: ArrayView2<f32>,
-        t: f32,
+        x: ArrayView2<Float>,
+        y: ArrayView2<Float>,
+        t: Float,
         vortex_param: VortexParameters,
     ) {
         assert_eq!(x.shape(), y.shape());
@@ -251,14 +252,18 @@ impl Field {
                x in x,
                y in y)
         {
+            #[cfg(feature = "f32")]
             use std::f32::consts::PI;
+            #[cfg(not(feature = "f32"))]
+            use std::f64::consts::PI;
+
             let dx = (x - vortex_param.x0) - t;
             let dy = y - vortex_param.y0;
             let f = (1.0 - (dx*dx + dy*dy))/(rstar*rstar);
 
-            *rho = f32::powf(1.0 - eps*eps*(GAMMA - 1.0)*m*m/(8.0*PI*PI*p_inf*rstar*rstar)*f.exp(), 1.0/(GAMMA - 1.0));
+            *rho = Float::powf(1.0 - eps*eps*(GAMMA - 1.0)*m*m/(8.0*PI*PI*p_inf*rstar*rstar)*f.exp(), 1.0/(GAMMA - 1.0));
             assert!(*rho > 0.0);
-            let p = f32::powf(*rho, GAMMA)*p_inf;
+            let p = Float::powf(*rho, GAMMA)*p_inf;
             assert!(p > 0.0);
             let u = 1.0 - eps*dy/(2.0*PI*p_inf.sqrt()*rstar*rstar)*(f/2.0).exp();
             let v =       eps*dx/(2.0*PI*p_inf.sqrt()*rstar*rstar)*(f/2.0).exp();
@@ -271,7 +276,7 @@ impl Field {
 
 impl Field {
     /// sqrt((self-other)^T*H*(self-other))
-    pub fn h2_err<SBP: SbpOperator>(&self, other: &Self) -> f32 {
+    pub fn h2_err<SBP: SbpOperator>(&self, other: &Self) -> Float {
         assert_eq!(self.nx(), other.nx());
         assert_eq!(self.ny(), other.ny());
 
@@ -285,7 +290,7 @@ impl Field {
 
         // This chains the h block into the form [h, 1, 1, 1, rev(h)],
         // and multiplies with a factor
-        let itermaker = move |n: usize, factor: f32| {
+        let itermaker = move |n: usize, factor: Float| {
             h.iter()
                 .copied()
                 .chain(std::iter::repeat(1.0).take(n - 2 * h.len()))
@@ -293,12 +298,12 @@ impl Field {
                 .map(move |x| x * factor)
         };
 
-        let hxiterator = itermaker(self.nx(), 1.0 / (self.nx() - 1) as f32);
+        let hxiterator = itermaker(self.nx(), 1.0 / (self.nx() - 1) as Float);
         // Repeating to get the form
         // [[hx0, hx1, ..., hxn], [hx0, hx1, ..., hxn], ..., [hx0, hx1, ..., hxn]]
         let hxiterator = hxiterator.into_iter().cycle().take(self.nx() * self.ny());
 
-        let hyiterator = itermaker(self.ny(), 1.0 / (self.ny() - 1) as f32);
+        let hyiterator = itermaker(self.ny(), 1.0 / (self.ny() - 1) as Float);
         // Repeating to get the form
         // [[hy0, hy0, ..., hy0], [hy1, hy1, ..., hy1], ..., [hym, hym, ..., hym]]
         let hyiterator = hyiterator
@@ -312,7 +317,7 @@ impl Field {
             .zip(self.0.iter())
             .zip(other.0.iter())
             .map(|(((hx, hy), r0), r1)| (*r0 - *r1).powi(2) * hx * hy)
-            .sum::<f32>()
+            .sum::<Float>()
             .sqrt()
     }
 }
@@ -333,14 +338,14 @@ fn h2_diff() {
 
 #[derive(Copy, Clone)]
 pub struct VortexParameters {
-    pub x0: f32,
-    pub y0: f32,
-    pub rstar: f32,
-    pub eps: f32,
-    pub mach: f32,
+    pub x0: Float,
+    pub y0: Float,
+    pub rstar: Float,
+    pub eps: Float,
+    pub mach: Float,
 }
 
-fn pressure(gamma: f32, rho: f32, rhou: f32, rhov: f32, e: f32) -> f32 {
+fn pressure(gamma: Float, rho: Float, rhou: Float, rhov: Float, e: Float) -> Float {
     (gamma - 1.0) * (e - (rhou * rhou + rhov * rhov) / (2.0 * rho))
 }
 
@@ -534,10 +539,10 @@ fn fluxes<SBP: SbpOperator>(k: (&mut Field, &mut Field), y: &Field, grid: &Grid<
 
 #[derive(Clone, Debug)]
 pub struct BoundaryTerms<'a> {
-    pub north: ArrayView2<'a, f32>,
-    pub south: ArrayView2<'a, f32>,
-    pub east: ArrayView2<'a, f32>,
-    pub west: ArrayView2<'a, f32>,
+    pub north: ArrayView2<'a, Float>,
+    pub south: ArrayView2<'a, Float>,
+    pub east: ArrayView2<'a, Float>,
+    pub west: ArrayView2<'a, Float>,
 }
 
 #[allow(non_snake_case)]
@@ -550,7 +555,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
 ) {
     // North boundary
     {
-        let hi = (k.ny() - 1) as f32 * SBP::h()[0];
+        let hi = (k.ny() - 1) as Float * SBP::h()[0];
         let sign = -1.0;
         let tau = 1.0;
         let slice = s![y.ny() - 1, ..];
@@ -568,7 +573,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
     }
     // South boundary
     {
-        let hi = (k.ny() - 1) as f32 * SBP::h()[0];
+        let hi = (k.ny() - 1) as Float * SBP::h()[0];
         let sign = 1.0;
         let tau = -1.0;
         let slice = s![0, ..];
@@ -586,7 +591,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
     }
     // West Boundary
     {
-        let hi = (k.nx() - 1) as f32 * SBP::h()[0];
+        let hi = (k.nx() - 1) as Float * SBP::h()[0];
         let sign = 1.0;
         let tau = -1.0;
         let slice = s![.., 0];
@@ -604,7 +609,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
     }
     // East Boundary
     {
-        let hi = (k.nx() - 1) as f32 * SBP::h()[0];
+        let hi = (k.nx() - 1) as Float * SBP::h()[0];
         let sign = -1.0;
         let tau = 1.0;
         let slice = s![.., y.nx() - 1];
@@ -627,15 +632,15 @@ fn SAT_characteristics<SBP: SbpOperator>(
 #[allow(clippy::too_many_arguments)]
 /// Boundary conditions (SAT)
 fn SAT_characteristic(
-    mut k: ArrayViewMut2<f32>,
-    y: ArrayView2<f32>,
-    z: ArrayView2<f32>, // Size 4 x n (all components in line)
-    hi: f32,
-    sign: f32,
-    tau: f32,
-    detj: ArrayView1<f32>,
-    detj_d_dx: ArrayView1<f32>,
-    detj_d_dy: ArrayView1<f32>,
+    mut k: ArrayViewMut2<Float>,
+    y: ArrayView2<Float>,
+    z: ArrayView2<Float>, // Size 4 x n (all components in line)
+    hi: Float,
+    sign: Float,
+    tau: Float,
+    detj: ArrayView1<Float>,
+    detj_d_dx: ArrayView1<Float>,
+    detj_d_dy: ArrayView1<Float>,
 ) {
     assert_eq!(detj.shape(), detj_d_dx.shape());
     assert_eq!(detj.shape(), detj_d_dy.shape());
@@ -660,7 +665,7 @@ fn SAT_characteristic(
         let ky_ = detj_d_dy / detj;
 
         let (kx, ky) = {
-            let r = f32::hypot(kx_, ky_);
+            let r = Float::hypot(kx_, ky_);
             (kx_ / r, ky_ / r)
         };
 
@@ -690,8 +695,8 @@ fn SAT_characteristic(
         let L = [
             U,
             U,
-            U + c * f32::hypot(kx_, ky_),
-            U - c * f32::hypot(kx_, ky_),
+            U + c * Float::hypot(kx_, ky_),
+            U - c * Float::hypot(kx_, ky_),
         ];
         let beta = 1.0 / (2.0 * c * c);
         let TI = [
diff --git a/sbp/src/grid.rs b/sbp/src/grid.rs
index 126ab0e..8c0cdec 100644
--- a/sbp/src/grid.rs
+++ b/sbp/src/grid.rs
@@ -1,3 +1,4 @@
+use crate::Float;
 use ndarray::Array2;
 
 #[derive(Debug, Clone)]
@@ -5,20 +6,20 @@ pub struct Grid<SBP>
 where
     SBP: super::operators::SbpOperator,
 {
-    pub(crate) x: Array2<f32>,
-    pub(crate) y: Array2<f32>,
+    pub(crate) x: Array2<Float>,
+    pub(crate) y: Array2<Float>,
 
-    pub(crate) detj: Array2<f32>,
-    pub(crate) detj_dxi_dx: Array2<f32>,
-    pub(crate) detj_dxi_dy: Array2<f32>,
-    pub(crate) detj_deta_dx: Array2<f32>,
-    pub(crate) detj_deta_dy: Array2<f32>,
+    pub(crate) detj: Array2<Float>,
+    pub(crate) detj_dxi_dx: Array2<Float>,
+    pub(crate) detj_dxi_dy: Array2<Float>,
+    pub(crate) detj_deta_dx: Array2<Float>,
+    pub(crate) detj_deta_dy: Array2<Float>,
 
     operator: std::marker::PhantomData<SBP>,
 }
 
 impl<SBP: super::operators::SbpOperator> Grid<SBP> {
-    pub fn new(x: Array2<f32>, y: Array2<f32>) -> Result<Self, ndarray::ShapeError> {
+    pub fn new(x: Array2<Float>, y: Array2<Float>) -> Result<Self, ndarray::ShapeError> {
         assert_eq!(x.shape(), y.shape());
         let ny = x.shape()[0];
         let nx = x.shape()[1];
diff --git a/sbp/src/integrate.rs b/sbp/src/integrate.rs
index dcd691c..7969561 100644
--- a/sbp/src/integrate.rs
+++ b/sbp/src/integrate.rs
@@ -1,17 +1,18 @@
 use super::grid::Grid;
 use super::operators::SbpOperator;
+use super::Float;
 use ndarray::{Array3, Zip};
 
 pub(crate) fn rk4<'a, F: 'a, SBP, RHS, WB>(
     rhs: RHS,
     prev: &F,
     fut: &mut F,
-    dt: f32,
+    dt: Float,
     grid: &Grid<SBP>,
     k: &mut [F; 4],
     mut wb: &mut WB,
 ) where
-    F: std::ops::Deref<Target = Array3<f32>> + std::ops::DerefMut<Target = Array3<f32>>,
+    F: std::ops::Deref<Target = Array3<Float>> + std::ops::DerefMut<Target = Array3<Float>>,
     SBP: SbpOperator,
     RHS: Fn(&mut F, &F, &Grid<SBP>, &mut WB),
 {
diff --git a/sbp/src/lib.rs b/sbp/src/lib.rs
index e27982a..9438284 100644
--- a/sbp/src/lib.rs
+++ b/sbp/src/lib.rs
@@ -1,3 +1,8 @@
+#[cfg(feature = "f32")]
+pub type Float = f32;
+#[cfg(not(feature = "f32"))]
+pub type Float = f64;
+
 pub mod euler;
 pub mod grid;
 pub mod integrate;
diff --git a/sbp/src/maxwell.rs b/sbp/src/maxwell.rs
index 3e98063..ac46dc3 100644
--- a/sbp/src/maxwell.rs
+++ b/sbp/src/maxwell.rs
@@ -1,14 +1,15 @@
 use super::grid::Grid;
 use super::integrate;
 use super::operators::{SbpOperator, UpwindOperator};
+use crate::Float;
 use ndarray::azip;
 use ndarray::prelude::*;
 
 #[derive(Clone, Debug)]
-pub struct Field(pub(crate) Array3<f32>);
+pub struct Field(pub(crate) Array3<Float>);
 
 impl std::ops::Deref for Field {
-    type Target = Array3<f32>;
+    type Target = Array3<Float>;
     fn deref(&self) -> &Self::Target {
         &self.0
     }
@@ -34,29 +35,33 @@ impl Field {
         self.0.shape()[1]
     }
 
-    pub fn ex(&self) -> ArrayView2<f32> {
+    pub fn ex(&self) -> ArrayView2<Float> {
         self.slice(s![0, .., ..])
     }
-    pub fn hz(&self) -> ArrayView2<f32> {
+    pub fn hz(&self) -> ArrayView2<Float> {
         self.slice(s![1, .., ..])
     }
-    pub fn ey(&self) -> ArrayView2<f32> {
+    pub fn ey(&self) -> ArrayView2<Float> {
         self.slice(s![2, .., ..])
     }
 
-    pub fn ex_mut(&mut self) -> ArrayViewMut2<f32> {
+    pub fn ex_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![0, .., ..])
     }
-    pub fn hz_mut(&mut self) -> ArrayViewMut2<f32> {
+    pub fn hz_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![1, .., ..])
     }
-    pub fn ey_mut(&mut self) -> ArrayViewMut2<f32> {
+    pub fn ey_mut(&mut self) -> ArrayViewMut2<Float> {
         self.slice_mut(s![2, .., ..])
     }
 
     pub fn components_mut(
         &mut self,
-    ) -> (ArrayViewMut2<f32>, ArrayViewMut2<f32>, ArrayViewMut2<f32>) {
+    ) -> (
+        ArrayViewMut2<Float>,
+        ArrayViewMut2<Float>,
+        ArrayViewMut2<Float>,
+    ) {
         let mut iter = self.0.outer_iter_mut();
 
         let ex = iter.next().unwrap();
@@ -76,7 +81,7 @@ pub struct System<SBP: SbpOperator> {
 }
 
 impl<SBP: SbpOperator> System<SBP> {
-    pub fn new(x: Array2<f32>, y: Array2<f32>) -> Self {
+    pub fn new(x: Array2<Float>, y: Array2<Float>) -> Self {
         assert_eq!(x.shape(), y.shape());
         let ny = x.shape()[0];
         let nx = x.shape()[1];
@@ -94,7 +99,7 @@ impl<SBP: SbpOperator> System<SBP> {
         &self.sys.0
     }
 
-    pub fn set_gaussian(&mut self, x0: f32, y0: f32) {
+    pub fn set_gaussian(&mut self, x0: Float, y0: Float) {
         let (ex, hz, ey) = self.sys.0.components_mut();
         ndarray::azip!(
             (ex in ex, hz in hz, ey in ey,
@@ -106,7 +111,7 @@ impl<SBP: SbpOperator> System<SBP> {
         });
     }
 
-    pub fn advance(&mut self, dt: f32) {
+    pub fn advance(&mut self, dt: Float) {
         integrate::rk4(
             RHS,
             &self.sys.0,
@@ -122,7 +127,7 @@ impl<SBP: SbpOperator> System<SBP> {
 
 impl<UO: UpwindOperator> System<UO> {
     /// Using artificial dissipation with the upwind operator
-    pub fn advance_upwind(&mut self, dt: f32) {
+    pub fn advance_upwind(&mut self, dt: Float) {
         integrate::rk4(
             RHS_upwind,
             &self.sys.0,
@@ -136,14 +141,18 @@ impl<UO: UpwindOperator> System<UO> {
     }
 }
 
-fn gaussian(x: f32, x0: f32, y: f32, y0: f32) -> f32 {
-    use std::f32;
+fn gaussian(x: Float, x0: Float, y: Float, y0: Float) -> Float {
+    #[cfg(feature = "f32")]
+    use std::f32::consts::PI;
+    #[cfg(not(feature = "f32"))]
+    use std::f64::consts::PI;
+
     let x = x - x0;
     let y = y - y0;
 
     let sigma = 0.05;
 
-    1.0 / (2.0 * f32::consts::PI * sigma * sigma) * (-(x * x + y * y) / (2.0 * sigma * sigma)).exp()
+    1.0 / (2.0 * PI * sigma * sigma) * (-(x * x + y * y) / (2.0 * sigma * sigma)).exp()
 }
 
 #[allow(non_snake_case)]
@@ -166,7 +175,7 @@ fn RHS<SBP: SbpOperator>(
     k: &mut Field,
     y: &Field,
     grid: &Grid<SBP>,
-    tmp: &mut (Array2<f32>, Array2<f32>, Array2<f32>, Array2<f32>),
+    tmp: &mut (Array2<Float>, Array2<Float>, Array2<Float>, Array2<Float>),
 ) {
     fluxes(k, y, grid, tmp);
 
@@ -189,7 +198,7 @@ fn RHS_upwind<UO: UpwindOperator>(
     k: &mut Field,
     y: &Field,
     grid: &Grid<UO>,
-    tmp: &mut (Array2<f32>, Array2<f32>, Array2<f32>, Array2<f32>),
+    tmp: &mut (Array2<Float>, Array2<Float>, Array2<Float>, Array2<Float>),
 ) {
     fluxes(k, y, grid, tmp);
     dissipation(k, y, grid, tmp);
@@ -212,7 +221,7 @@ fn fluxes<SBP: SbpOperator>(
     k: &mut Field,
     y: &Field,
     grid: &Grid<SBP>,
-    tmp: &mut (Array2<f32>, Array2<f32>, Array2<f32>, Array2<f32>),
+    tmp: &mut (Array2<Float>, Array2<Float>, Array2<Float>, Array2<Float>),
 ) {
     // ex = hz_y
     {
@@ -286,7 +295,7 @@ fn dissipation<UO: UpwindOperator>(
     k: &mut Field,
     y: &Field,
     grid: &Grid<UO>,
-    tmp: &mut (Array2<f32>, Array2<f32>, Array2<f32>, Array2<f32>),
+    tmp: &mut (Array2<Float>, Array2<Float>, Array2<Float>, Array2<Float>),
 ) {
     // ex component
     {
@@ -295,7 +304,7 @@ fn dissipation<UO: UpwindOperator>(
                         &ky in &grid.detj_dxi_dy,
                         &ex in &y.ex(),
                         &ey in &y.ey()) {
-            let r = f32::hypot(kx, ky);
+            let r = Float::hypot(kx, ky);
             *a = ky*ky/r * ex + -kx*ky/r*ey;
         });
         UO::dissxi(tmp.0.view(), tmp.1.view_mut());
@@ -305,7 +314,7 @@ fn dissipation<UO: UpwindOperator>(
                     &ky in &grid.detj_deta_dy,
                     &ex in &y.ex(),
                     &ey in &y.ey()) {
-            let r = f32::hypot(kx, ky);
+            let r = Float::hypot(kx, ky);
             *b = ky*ky/r * ex + -kx*ky/r*ey;
         });
         UO::disseta(tmp.2.view(), tmp.3.view_mut());
@@ -321,7 +330,7 @@ fn dissipation<UO: UpwindOperator>(
                         &kx in &grid.detj_dxi_dx,
                         &ky in &grid.detj_dxi_dy,
                         &hz in &y.hz()) {
-            let r = f32::hypot(kx, ky);
+            let r = Float::hypot(kx, ky);
             *a = r * hz;
         });
         UO::dissxi(tmp.0.view(), tmp.1.view_mut());
@@ -330,7 +339,7 @@ fn dissipation<UO: UpwindOperator>(
                         &kx in &grid.detj_deta_dx,
                         &ky in &grid.detj_deta_dy,
                         &hz in &y.hz()) {
-            let r = f32::hypot(kx, ky);
+            let r = Float::hypot(kx, ky);
             *b = r * hz;
         });
         UO::disseta(tmp.2.view(), tmp.3.view_mut());
@@ -347,7 +356,7 @@ fn dissipation<UO: UpwindOperator>(
                         &ky in &grid.detj_dxi_dy,
                         &ex in &y.ex(),
                         &ey in &y.ey()) {
-            let r = f32::hypot(kx, ky);
+            let r = Float::hypot(kx, ky);
             *a = -kx*ky/r * ex + kx*kx/r*ey;
         });
         UO::dissxi(tmp.0.view(), tmp.1.view_mut());
@@ -357,7 +366,7 @@ fn dissipation<UO: UpwindOperator>(
                     &ky in &grid.detj_deta_dy,
                     &ex in &y.ex(),
                     &ey in &y.ey()) {
-            let r = f32::hypot(kx, ky);
+            let r = Float::hypot(kx, ky);
             *b = -kx*ky/r * ex + kx*kx/r*ey;
         });
         UO::disseta(tmp.2.view(), tmp.3.view_mut());
@@ -392,7 +401,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
     let ny = y.ny();
     let nx = y.nx();
 
-    fn positive_flux(kx: f32, ky: f32) -> [[f32; 3]; 3] {
+    fn positive_flux(kx: Float, ky: Float) -> [[Float; 3]; 3] {
         let r = (kx * kx + ky * ky).sqrt();
         [
             [ky * ky / r / 2.0, ky / 2.0, -kx * ky / r / 2.0],
@@ -400,7 +409,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
             [-kx * ky / r / 2.0, -kx / 2.0, kx * kx / r / 2.0],
         ]
     }
-    fn negative_flux(kx: f32, ky: f32) -> [[f32; 3]; 3] {
+    fn negative_flux(kx: Float, ky: Float) -> [[Float; 3]; 3] {
         let r = (kx * kx + ky * ky).sqrt();
         [
             [-ky * ky / r / 2.0, ky / 2.0, kx * ky / r / 2.0],
@@ -414,7 +423,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
             Boundary::This => y.slice(s![.., .., 0]),
         };
         // East boundary
-        let hinv = 1.0 / (SBP::h()[0] / (nx - 1) as f32);
+        let hinv = 1.0 / (SBP::h()[0] / (nx - 1) as Float);
         for ((((mut k, v), g), &kx), &ky) in k
             .slice_mut(s![.., .., nx - 1])
             .gencolumns_mut()
@@ -448,7 +457,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
         let g = match boundaries.east {
             Boundary::This => y.slice(s![.., .., nx - 1]),
         };
-        let hinv = 1.0 / (SBP::h()[0] / (nx - 1) as f32);
+        let hinv = 1.0 / (SBP::h()[0] / (nx - 1) as Float);
         for ((((mut k, v), g), &kx), &ky) in k
             .slice_mut(s![.., .., 0])
             .gencolumns_mut()
@@ -487,7 +496,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
         let g = match boundaries.north {
             Boundary::This => y.slice(s![.., 0, ..]),
         };
-        let hinv = 1.0 / (SBP::h()[0] / (ny - 1) as f32);
+        let hinv = 1.0 / (SBP::h()[0] / (ny - 1) as Float);
         for ((((mut k, v), g), &kx), &ky) in k
             .slice_mut(s![.., ny - 1, ..])
             .gencolumns_mut()
@@ -520,7 +529,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
         let g = match boundaries.south {
             Boundary::This => y.slice(s![.., ny - 1, ..]),
         };
-        let hinv = 1.0 / (SBP::h()[0] / (ny - 1) as f32);
+        let hinv = 1.0 / (SBP::h()[0] / (ny - 1) as Float);
         for ((((mut k, v), g), &kx), &ky) in k
             .slice_mut(s![.., 0, ..])
             .gencolumns_mut()
@@ -560,7 +569,7 @@ fn SAT_characteristics<SBP: SbpOperator>(
 #[derive(Clone, Debug)]
 pub struct WorkBuffers {
     k: [Field; 4],
-    tmp: (Array2<f32>, Array2<f32>, Array2<f32>, Array2<f32>),
+    tmp: (Array2<Float>, Array2<Float>, Array2<Float>, Array2<Float>),
 }
 
 impl WorkBuffers {
diff --git a/sbp/src/operators.rs b/sbp/src/operators.rs
index e128b73..1457429 100644
--- a/sbp/src/operators.rs
+++ b/sbp/src/operators.rs
@@ -1,29 +1,31 @@
 #![allow(clippy::excessive_precision)]
 #![allow(clippy::unreadable_literal)]
 
+use crate::Float;
+
 use ndarray::{ArrayView2, ArrayViewMut2};
 
 pub trait SbpOperator {
-    fn diffxi(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>);
-    fn diffeta(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>);
-    fn h() -> &'static [f32];
+    fn diffxi(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>);
+    fn diffeta(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>);
+    fn h() -> &'static [Float];
 }
 
 pub trait UpwindOperator: SbpOperator {
-    fn dissxi(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>);
-    fn disseta(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>);
+    fn dissxi(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>);
+    fn disseta(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>);
 }
 
 #[macro_export]
 macro_rules! diff_op_1d {
     ($self: ty, $name: ident, $BLOCK: expr, $DIAG: expr, $symmetric: expr) => {
         impl $self {
-            fn $name(prev: ArrayView1<f32>, mut fut: ArrayViewMut1<f32>) {
+            fn $name(prev: ArrayView1<Float>, mut fut: ArrayViewMut1<Float>) {
                 assert_eq!(prev.shape(), fut.shape());
                 let nx = prev.shape()[0];
                 assert!(nx >= 2 * $BLOCK.len());
 
-                let dx = 1.0 / (nx - 1) as f32;
+                let dx = 1.0 / (nx - 1) as Float;
                 let idx = 1.0 / dx;
 
                 let block = ::ndarray::arr2($BLOCK);
diff --git a/sbp/src/operators/traditional4.rs b/sbp/src/operators/traditional4.rs
index 10051f1..f1b546b 100644
--- a/sbp/src/operators/traditional4.rs
+++ b/sbp/src/operators/traditional4.rs
@@ -1,5 +1,6 @@
 use super::SbpOperator;
 use crate::diff_op_1d;
+use crate::Float;
 use ndarray::{s, ArrayView1, ArrayView2, ArrayViewMut1, ArrayViewMut2};
 
 #[derive(Debug)]
@@ -9,15 +10,15 @@ diff_op_1d!(SBP4, diff_1d, SBP4::BLOCK, SBP4::DIAG, false);
 
 impl SBP4 {
     #[rustfmt::skip]
-    const HBLOCK: &'static [f32] = &[
+    const HBLOCK: &'static [Float] = &[
         17.0 / 48.0, 59.0 / 48.0, 43.0 / 48.0, 49.0 / 48.0,
     ];
     #[rustfmt::skip]
-    const DIAG: &'static [f32] = &[
+    const DIAG: &'static [Float] = &[
         1.0 / 12.0, -2.0 / 3.0, 0.0, 2.0 / 3.0, -1.0 / 12.0,
     ];
     #[rustfmt::skip]
-    const BLOCK: &'static [[f32; 6]] = &[
+    const BLOCK: &'static [[Float; 6]] = &[
         [-1.41176470588235e+00, 1.73529411764706e+00, -2.35294117647059e-01, -8.82352941176471e-02, 0.00000000000000e+00, 0.00000000000000e+00],
         [-5.00000000000000e-01, 0.00000000000000e+00, 5.00000000000000e-01, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
         [9.30232558139535e-02, -6.86046511627907e-01, 0.00000000000000e+00, 6.86046511627907e-01, -9.30232558139535e-02, 0.00000000000000e+00],
@@ -26,7 +27,7 @@ impl SBP4 {
 }
 
 impl SbpOperator for SBP4 {
-    fn diffxi(prev: ArrayView2<f32>, mut fut: ArrayViewMut2<f32>) {
+    fn diffxi(prev: ArrayView2<Float>, mut fut: ArrayViewMut2<Float>) {
         assert_eq!(prev.shape(), fut.shape());
         assert!(prev.shape()[1] >= 2 * Self::BLOCK.len());
 
@@ -35,12 +36,12 @@ impl SbpOperator for SBP4 {
         }
     }
 
-    fn diffeta(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>) {
+    fn diffeta(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>) {
         // transpose then use diffxi
         Self::diffxi(prev.reversed_axes(), fut.reversed_axes());
     }
 
-    fn h() -> &'static [f32] {
+    fn h() -> &'static [Float] {
         Self::HBLOCK
     }
 }
diff --git a/sbp/src/operators/traditional8.rs b/sbp/src/operators/traditional8.rs
index eb656ad..fb390cc 100644
--- a/sbp/src/operators/traditional8.rs
+++ b/sbp/src/operators/traditional8.rs
@@ -1,5 +1,6 @@
 use super::SbpOperator;
 use crate::diff_op_1d;
+use crate::Float;
 use ndarray::{s, ArrayView1, ArrayView2, ArrayViewMut1, ArrayViewMut2};
 
 #[derive(Debug)]
@@ -9,15 +10,15 @@ diff_op_1d!(SBP8, diff_1d, SBP8::BLOCK, SBP8::DIAG, false);
 
 impl SBP8 {
     #[rustfmt::skip]
-    const HBLOCK: &'static [f32] = &[
+    const HBLOCK: &'static [Float] = &[
         2.94890676177879e-01, 1.52572062389771e+00, 2.57452876984127e-01, 1.79811370149912e+00, 4.12708057760141e-01, 1.27848462301587e+00, 9.23295579805997e-01, 1.00933386085916e+00
     ];
     #[rustfmt::skip]
-    const DIAG: &'static [f32] = &[
+    const DIAG: &'static [Float] = &[
         3.57142857142857e-03, -3.80952380952381e-02, 2.00000000000000e-01, -8.00000000000000e-01, -0.00000000000000e+00, 8.00000000000000e-01, -2.00000000000000e-01, 3.80952380952381e-02, -3.57142857142857e-03
     ];
     #[rustfmt::skip]
-    const BLOCK: &'static [[f32; 12]] = &[
+    const BLOCK: &'static [[Float; 12]] = &[
         [-1.69554360443190e+00, 2.24741246341404e+00, -3.38931922601500e-02, -7.81028168126749e-01, 2.54881486107905e-02, 3.43865227388873e-01, -8.62858162633335e-02, -2.00150583315761e-02, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
         [-4.34378988266985e-01, 0.00000000000000e+00, 9.18511925072956e-02, 4.94008626807984e-01, -2.46151762937235e-02, -1.86759403432935e-01, 5.27267838475813e-02, 7.16696483080115e-03, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
         [3.88218088704253e-02, -5.44329744454984e-01, 0.00000000000000e+00, 3.89516189693211e-01, 1.36433486528546e-01, 1.03290582800845e-01, -1.79720579323281e-01, 5.59882558852296e-02, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
@@ -30,7 +31,7 @@ impl SBP8 {
 }
 
 impl SbpOperator for SBP8 {
-    fn diffxi(prev: ArrayView2<f32>, mut fut: ArrayViewMut2<f32>) {
+    fn diffxi(prev: ArrayView2<Float>, mut fut: ArrayViewMut2<Float>) {
         assert_eq!(prev.shape(), fut.shape());
         assert!(prev.shape()[1] >= 2 * Self::BLOCK.len());
 
@@ -39,12 +40,12 @@ impl SbpOperator for SBP8 {
         }
     }
 
-    fn diffeta(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>) {
+    fn diffeta(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>) {
         // transpose then use diffxi
         Self::diffxi(prev.reversed_axes(), fut.reversed_axes());
     }
 
-    fn h() -> &'static [f32] {
+    fn h() -> &'static [Float] {
         Self::HBLOCK
     }
 }
diff --git a/sbp/src/operators/upwind4.rs b/sbp/src/operators/upwind4.rs
index 95633ec..34aea39 100644
--- a/sbp/src/operators/upwind4.rs
+++ b/sbp/src/operators/upwind4.rs
@@ -1,12 +1,16 @@
 use super::{SbpOperator, UpwindOperator};
 use crate::diff_op_1d;
+use crate::Float;
 use ndarray::{s, ArrayView1, ArrayView2, ArrayViewMut1, ArrayViewMut2, Axis};
 
 #[derive(Debug)]
 pub struct Upwind4 {}
 
 /// Simdtype used in diff_simd_col
+#[cfg(feature = "f32")]
 type SimdT = packed_simd::f32x8;
+#[cfg(not(feature = "f32"))]
+type SimdT = packed_simd::f64x8;
 
 diff_op_1d!(Upwind4, diff_1d, Upwind4::BLOCK, Upwind4::DIAG, false);
 diff_op_1d!(
@@ -21,44 +25,48 @@ macro_rules! diff_simd_row_7_47 {
     ($self: ident, $name: ident, $BLOCK: expr, $DIAG: expr, $symmetric: expr) => {
         impl $self {
             #[inline(never)]
-            fn $name(prev: ArrayView2<f32>, mut fut: ArrayViewMut2<f32>) {
-                use packed_simd::{f32x8, u32x8};
+            fn $name(prev: ArrayView2<Float>, mut fut: ArrayViewMut2<Float>) {
+                #[cfg(feature = "f32")]
+                type SimdIndex = packed_simd::u32x8;
+                #[cfg(not(feature = "f32"))]
+                type SimdIndex = packed_simd::u64x8;
                 assert_eq!(prev.shape(), fut.shape());
                 assert!(prev.len_of(Axis(1)) >= 2 * $BLOCK.len());
-                assert!(prev.len() >= f32x8::lanes());
+                assert!(prev.len() >= SimdT::lanes());
                 // The prev and fut array must have contigous last dimension
                 assert_eq!(prev.strides()[1], 1);
                 assert_eq!(fut.strides()[1], 1);
 
                 let nx = prev.len_of(Axis(1));
-                let dx = 1.0 / (nx - 1) as f32;
+                let dx = 1.0 / (nx - 1) as Float;
                 let idx = 1.0 / dx;
 
                 for j in 0..prev.len_of(Axis(0)) {
                     use std::slice;
                     let prev =
-                        unsafe { slice::from_raw_parts(prev.uget((j, 0)) as *const f32, nx) };
-                    let fut =
-                        unsafe { slice::from_raw_parts_mut(fut.uget_mut((j, 0)) as *mut f32, nx) };
+                        unsafe { slice::from_raw_parts(prev.uget((j, 0)) as *const Float, nx) };
+                    let fut = unsafe {
+                        slice::from_raw_parts_mut(fut.uget_mut((j, 0)) as *mut Float, nx)
+                    };
                     //let mut fut = fut.slice_mut(s![j, ..]);
 
-                    let first_elems = unsafe { f32x8::from_slice_unaligned_unchecked(prev) };
+                    let first_elems = unsafe { SimdT::from_slice_unaligned_unchecked(prev) };
                     let block = {
                         let bl = $BLOCK;
                         [
-                            f32x8::new(
+                            SimdT::new(
                                 bl[0][0], bl[0][1], bl[0][2], bl[0][3], bl[0][4], bl[0][5],
                                 bl[0][6], 0.0,
                             ),
-                            f32x8::new(
+                            SimdT::new(
                                 bl[1][0], bl[1][1], bl[1][2], bl[1][3], bl[1][4], bl[1][5],
                                 bl[1][6], 0.0,
                             ),
-                            f32x8::new(
+                            SimdT::new(
                                 bl[2][0], bl[2][1], bl[2][2], bl[2][3], bl[2][4], bl[2][5],
                                 bl[2][6], 0.0,
                             ),
-                            f32x8::new(
+                            SimdT::new(
                                 bl[3][0], bl[3][1], bl[3][2], bl[3][3], bl[3][4], bl[3][5],
                                 bl[3][6], 0.0,
                             ),
@@ -71,7 +79,7 @@ macro_rules! diff_simd_row_7_47 {
 
                     let diag = {
                         let diag = $DIAG;
-                        f32x8::new(
+                        SimdT::new(
                             diag[0], diag[1], diag[2], diag[3], diag[4], diag[5], diag[6], 0.0,
                         )
                     };
@@ -79,8 +87,8 @@ macro_rules! diff_simd_row_7_47 {
                         .iter_mut()
                         .skip(block.len())
                         .zip(
-                            prev.windows(f32x8::lanes())
-                                .map(f32x8::from_slice_unaligned)
+                            prev.windows(SimdT::lanes())
+                                .map(SimdT::from_slice_unaligned)
                                 .skip(1),
                         )
                         .take(nx - 2 * block.len())
@@ -89,8 +97,8 @@ macro_rules! diff_simd_row_7_47 {
                     }
 
                     let last_elems =
-                        unsafe { f32x8::from_slice_unaligned_unchecked(&prev[nx - 8..]) }
-                            .shuffle1_dyn(u32x8::new(7, 6, 5, 4, 3, 2, 1, 0));
+                        unsafe { SimdT::from_slice_unaligned_unchecked(&prev[nx - 8..]) }
+                            .shuffle1_dyn(SimdIndex::new(7, 6, 5, 4, 3, 2, 1, 0));
                     if $symmetric {
                         fut[nx - 4] = idx * (block[3] * last_elems).sum();
                         fut[nx - 3] = idx * (block[2] * last_elems).sum();
@@ -121,7 +129,7 @@ macro_rules! diff_simd_col_7_47 {
     ($self: ident, $name: ident, $BLOCK: expr, $DIAG: expr, $symmetric: expr) => {
         impl $self {
             #[inline(never)]
-            fn $name(prev: ArrayView2<f32>, mut fut: ArrayViewMut2<f32>) {
+            fn $name(prev: ArrayView2<Float>, mut fut: ArrayViewMut2<Float>) {
                 use std::slice;
                 assert_eq!(prev.shape(), fut.shape());
                 assert_eq!(prev.stride_of(Axis(0)), 1);
@@ -132,38 +140,38 @@ macro_rules! diff_simd_col_7_47 {
                 assert!(ny >= SimdT::lanes());
                 assert!(ny % SimdT::lanes() == 0);
 
-                let dx = 1.0 / (nx - 1) as f32;
+                let dx = 1.0 / (nx - 1) as Float;
                 let idx = 1.0 / dx;
 
                 for j in (0..ny).step_by(SimdT::lanes()) {
                     let a = unsafe {
                         [
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, 0)) as *const f32,
+                                prev.uget((j, 0)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, 1)) as *const f32,
+                                prev.uget((j, 1)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, 2)) as *const f32,
+                                prev.uget((j, 2)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, 3)) as *const f32,
+                                prev.uget((j, 3)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, 4)) as *const f32,
+                                prev.uget((j, 4)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, 5)) as *const f32,
+                                prev.uget((j, 5)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, 6)) as *const f32,
+                                prev.uget((j, 6)) as *const Float,
                                 SimdT::lanes(),
                             )),
                         ]
@@ -180,7 +188,7 @@ macro_rules! diff_simd_col_7_47 {
                                 + a[6] * bl[6]);
                         unsafe {
                             b.write_to_slice_unaligned(slice::from_raw_parts_mut(
-                                fut.uget_mut((j, i)) as *mut f32,
+                                fut.uget_mut((j, i)) as *mut Float,
                                 SimdT::lanes(),
                             ));
                         }
@@ -191,7 +199,7 @@ macro_rules! diff_simd_col_7_47 {
                         // Push a onto circular buffer
                         a = [a[1], a[2], a[3], a[4], a[5], a[6], unsafe {
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, i + 3)) as *const f32,
+                                prev.uget((j, i + 3)) as *const Float,
                                 SimdT::lanes(),
                             ))
                         }];
@@ -205,7 +213,7 @@ macro_rules! diff_simd_col_7_47 {
                                 + a[6] * $DIAG[6]);
                         unsafe {
                             b.write_to_slice_unaligned(slice::from_raw_parts_mut(
-                                fut.uget_mut((j, i)) as *mut f32,
+                                fut.uget_mut((j, i)) as *mut Float,
                                 SimdT::lanes(),
                             ));
                         }
@@ -214,31 +222,31 @@ macro_rules! diff_simd_col_7_47 {
                     let a = unsafe {
                         [
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, nx - 1)) as *const f32,
+                                prev.uget((j, nx - 1)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, nx - 2)) as *const f32,
+                                prev.uget((j, nx - 2)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, nx - 3)) as *const f32,
+                                prev.uget((j, nx - 3)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, nx - 4)) as *const f32,
+                                prev.uget((j, nx - 4)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, nx - 5)) as *const f32,
+                                prev.uget((j, nx - 5)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, nx - 6)) as *const f32,
+                                prev.uget((j, nx - 6)) as *const Float,
                                 SimdT::lanes(),
                             )),
                             SimdT::from_slice_unaligned(slice::from_raw_parts(
-                                prev.uget((j, nx - 7)) as *const f32,
+                                prev.uget((j, nx - 7)) as *const Float,
                                 SimdT::lanes(),
                             )),
                         ]
@@ -256,7 +264,7 @@ macro_rules! diff_simd_col_7_47 {
                                 + a[6] * bl[6]);
                         unsafe {
                             b.write_to_slice_unaligned(slice::from_raw_parts_mut(
-                                fut.uget_mut((j, nx - 1 - i)) as *mut f32,
+                                fut.uget_mut((j, nx - 1 - i)) as *mut Float,
                                 SimdT::lanes(),
                             ));
                         }
@@ -278,15 +286,15 @@ diff_simd_col_7_47!(
 
 impl Upwind4 {
     #[rustfmt::skip]
-    const HBLOCK: &'static [f32] = &[
+    const HBLOCK: &'static [Float] = &[
         49.0 / 144.0, 61.0 / 48.0, 41.0 / 48.0, 149.0 / 144.0
     ];
     #[rustfmt::skip]
-    const DIAG: &'static [f32] = &[
+    const DIAG: &'static [Float] = &[
         -1.0 / 24.0, 1.0 / 4.0, -7.0 / 8.0, 0.0, 7.0 / 8.0, -1.0 / 4.0, 1.0 / 24.0
     ];
     #[rustfmt::skip]
-    const BLOCK: &'static [[f32; 7]] = &[
+    const BLOCK: &'static [[Float; 7]] = &[
         [  -72.0 / 49.0, 187.0 / 98.0,   -20.0 / 49.0,   -3.0 / 98.0,           0.0,           0.0,         0.0],
         [-187.0 / 366.0,          0.0,   69.0 / 122.0, -16.0 / 183.0,    2.0 / 61.0,           0.0,         0.0],
         [  20.0 / 123.0, -69.0 / 82.0,            0.0, 227.0 / 246.0,  -12.0 / 41.0,    2.0 / 41.0,         0.0],
@@ -294,7 +302,7 @@ impl Upwind4 {
     ];
 
     #[rustfmt::skip]
-    const DISS_BLOCK: &'static [[f32; 7]; 4] = &[
+    const DISS_BLOCK: &'static [[Float; 7]; 4] = &[
         [-3.0 / 49.0,    9.0 / 49.0,  -9.0 / 49.0,     3.0 / 49.0,          0.0,           0.0,         0.0],
         [ 3.0 / 61.0,  -11.0 / 61.0,  15.0 / 61.0,    -9.0 / 61.0,   2.0 / 61.0,           0.0,         0.0],
         [-3.0 / 41.0,   15.0 / 41.0, -29.0 / 41.0,    27.0 / 41.0, -12.0 / 41.0,    2.0 / 41.0,         0.0],
@@ -302,13 +310,13 @@ impl Upwind4 {
     ];
 
     #[rustfmt::skip]
-    const DISS_DIAG: &'static [f32; 7] = &[
+    const DISS_DIAG: &'static [Float; 7] = &[
         1.0 / 24.0, -1.0 / 4.0, 5.0 / 8.0, -5.0 / 6.0, 5.0 / 8.0, -1.0 / 4.0, 1.0 / 24.0
     ];
 }
 
 impl SbpOperator for Upwind4 {
-    fn diffxi(prev: ArrayView2<f32>, mut fut: ArrayViewMut2<f32>) {
+    fn diffxi(prev: ArrayView2<Float>, mut fut: ArrayViewMut2<Float>) {
         assert_eq!(prev.shape(), fut.shape());
         assert!(prev.shape()[1] >= 2 * Self::BLOCK.len());
 
@@ -329,12 +337,12 @@ impl SbpOperator for Upwind4 {
         }
     }
 
-    fn diffeta(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>) {
+    fn diffeta(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>) {
         // transpose then use diffxi
         Self::diffxi(prev.reversed_axes(), fut.reversed_axes());
     }
 
-    fn h() -> &'static [f32] {
+    fn h() -> &'static [Float] {
         Self::HBLOCK
     }
 }
@@ -343,13 +351,13 @@ impl SbpOperator for Upwind4 {
 fn upwind4_test() {
     use ndarray::prelude::*;
     let nx = 20;
-    let dx = 1.0 / (nx - 1) as f32;
-    let mut source: ndarray::Array1<f32> = ndarray::Array1::zeros(nx);
+    let dx = 1.0 / (nx - 1) as Float;
+    let mut source: ndarray::Array1<Float> = ndarray::Array1::zeros(nx);
     let mut res = ndarray::Array1::zeros(nx);
     let mut target = ndarray::Array1::zeros(nx);
 
     for i in 0..nx {
-        source[i] = i as f32 * dx;
+        source[i] = i as Float * dx;
         target[i] = 1.0;
     }
     res.fill(0.0);
@@ -374,7 +382,7 @@ fn upwind4_test() {
     }
 
     for i in 0..nx {
-        let x = i as f32 * dx;
+        let x = i as Float * dx;
         source[i] = x * x;
         target[i] = 2.0 * x;
     }
@@ -400,7 +408,7 @@ fn upwind4_test() {
     }
 
     for i in 0..nx {
-        let x = i as f32 * dx;
+        let x = i as Float * dx;
         source[i] = x * x * x;
         target[i] = 3.0 * x * x;
     }
@@ -428,7 +436,7 @@ fn upwind4_test() {
 }
 
 impl UpwindOperator for Upwind4 {
-    fn dissxi(prev: ArrayView2<f32>, mut fut: ArrayViewMut2<f32>) {
+    fn dissxi(prev: ArrayView2<Float>, mut fut: ArrayViewMut2<Float>) {
         assert_eq!(prev.shape(), fut.shape());
         assert!(prev.shape()[1] >= 2 * Self::BLOCK.len());
 
@@ -449,7 +457,7 @@ impl UpwindOperator for Upwind4 {
         }
     }
 
-    fn disseta(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>) {
+    fn disseta(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>) {
         // diffeta = transpose then use dissxi
         Self::dissxi(prev.reversed_axes(), fut.reversed_axes());
     }
diff --git a/sbp/src/operators/upwind9.rs b/sbp/src/operators/upwind9.rs
index d745641..d5cb69b 100644
--- a/sbp/src/operators/upwind9.rs
+++ b/sbp/src/operators/upwind9.rs
@@ -1,5 +1,6 @@
 use super::{SbpOperator, UpwindOperator};
 use crate::diff_op_1d;
+use crate::Float;
 use ndarray::{s, ArrayView1, ArrayView2, ArrayViewMut1, ArrayViewMut2};
 
 #[derive(Debug)]
@@ -16,15 +17,15 @@ diff_op_1d!(
 
 impl Upwind9 {
     #[rustfmt::skip]
-    const HBLOCK: &'static [f32] = &[
+    const HBLOCK: &'static [Float] = &[
         1070017.0/3628800.0, 5537111.0/3628800.0, 103613.0/403200.0, 261115.0/145152.0, 298951.0/725760.0, 515677.0/403200.0, 3349879.0/3628800.0, 3662753.0/3628800.0
     ];
     #[rustfmt::skip]
-    const DIAG: &'static [f32] = &[
+    const DIAG: &'static [Float] = &[
         -1.0/1260.0, 5.0/504.0, -5.0/84.0, 5.0/21.0, -5.0/6.0, 0.0, 5.0/6.0, -5.0/21.0, 5.0/84.0, -5.0/504.0, 1.0/1260.0,
     ];
     #[rustfmt::skip]
-    const BLOCK: &'static [[f32; 13]] = &[
+    const BLOCK: &'static [[Float; 13]] = &[
         [-1.69567399396458e+00, 2.29023358159400e+00, -2.16473500425698e-01, -5.05879766354449e-01, -1.01161106778154e-01, 2.59147072064383e-01, 1.93922119400659e-02, -4.95844980755642e-02, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
         [-4.42575354959737e-01, 0.00000000000000e+00, 1.91582959381899e-01, 2.82222626681305e-01, 1.12083989713257e-01, -1.51334868892111e-01, -2.23600502721044e-02, 3.03806983474913e-02, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
         [2.48392603571843e-01, -1.13758367065272e+00, 0.00000000000000e+00, 1.95334726810969e+00, -1.58879011773212e+00, 3.93797129320378e-01, 2.52140821030291e-01, -1.21304033647356e-01, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
@@ -36,7 +37,7 @@ impl Upwind9 {
     ];
 
     #[rustfmt::skip]
-    const DISS_BLOCK: &'static [[f32; 13]] = &[
+    const DISS_BLOCK: &'static [[Float; 13]] = &[
         [-3.99020778658945e-04, 2.05394169917502e-03, -4.24493243399805e-03, 4.38126393542801e-03, -2.18883813216888e-03, 2.98565988131608e-04, 1.38484104084115e-04, -3.94643819928825e-05, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
         [3.96913216138553e-04, -2.28230530115522e-03, 5.43069719436758e-03, -6.81086901935894e-03, 4.69064759201504e-03, -1.61429862514855e-03, 1.62083873811316e-04, 2.71310693302277e-05, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
         [-4.87084939816571e-03, 3.22464611075207e-02, -9.06094757860846e-02, 1.39830191253413e-01, -1.27675500367419e-01, 6.87310321912961e-02, -2.00917702215270e-02, 2.43991122096699e-03, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00, 0.00000000000000e+00],
@@ -48,13 +49,13 @@ impl Upwind9 {
     ];
 
     #[rustfmt::skip]
-    const DISS_DIAG: &'static [f32] = &[
+    const DISS_DIAG: &'static [Float] = &[
         1.0/1260.0, -1.0/126.0, 1.0/28.0, -2.0/21.0, 1.0/6.0, -1.0/5.0, 1.0/6.0, -2.0/21.0, 1.0/28.0, -1.0/126.0, 1.0/1260.0,
     ];
 }
 
 impl SbpOperator for Upwind9 {
-    fn diffxi(prev: ArrayView2<f32>, mut fut: ArrayViewMut2<f32>) {
+    fn diffxi(prev: ArrayView2<Float>, mut fut: ArrayViewMut2<Float>) {
         assert_eq!(prev.shape(), fut.shape());
         assert!(prev.shape()[1] >= 2 * Self::BLOCK.len());
 
@@ -63,18 +64,18 @@ impl SbpOperator for Upwind9 {
         }
     }
 
-    fn diffeta(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>) {
+    fn diffeta(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>) {
         // transpose then use diffxi
         Self::diffxi(prev.reversed_axes(), fut.reversed_axes());
     }
 
-    fn h() -> &'static [f32] {
+    fn h() -> &'static [Float] {
         Self::HBLOCK
     }
 }
 
 impl UpwindOperator for Upwind9 {
-    fn dissxi(prev: ArrayView2<f32>, mut fut: ArrayViewMut2<f32>) {
+    fn dissxi(prev: ArrayView2<Float>, mut fut: ArrayViewMut2<Float>) {
         assert_eq!(prev.shape(), fut.shape());
         assert!(prev.shape()[1] >= 2 * Self::BLOCK.len());
 
@@ -83,7 +84,7 @@ impl UpwindOperator for Upwind9 {
         }
     }
 
-    fn disseta(prev: ArrayView2<f32>, fut: ArrayViewMut2<f32>) {
+    fn disseta(prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>) {
         // diffeta = transpose then use dissxi
         Self::dissxi(prev.reversed_axes(), fut.reversed_axes());
     }
diff --git a/sbp/src/utils.rs b/sbp/src/utils.rs
index 459e5c9..fe4338c 100644
--- a/sbp/src/utils.rs
+++ b/sbp/src/utils.rs
@@ -1,7 +1,9 @@
+use crate::Float;
+
 #[derive(Debug, Clone)]
 pub struct SimpleGrid {
-    pub x: ndarray::Array2<f32>,
-    pub y: ndarray::Array2<f32>,
+    pub x: ndarray::Array2<Float>,
+    pub y: ndarray::Array2<Float>,
     pub name: Option<String>,
     pub dire: Option<String>,
     pub dirw: Option<String>,
@@ -32,9 +34,9 @@ pub fn json_to_grids(json: &str) -> Result<Vec<SimpleGrid>, String> {
         enum ArrayForm {
             /// Only know the one dimension, will broadcast to
             /// two dimensions once we know about both dims
-            Array1(ndarray::Array1<f32>),
+            Array1(ndarray::Array1<Float>),
             /// The usize is the inner dimension (nx)
-            Array2(ndarray::Array2<f32>),
+            Array2(ndarray::Array2<Float>),
         }
         if grid.is_empty() {
             return Err(format!("empty object"));
@@ -54,12 +56,12 @@ pub fn json_to_grids(json: &str) -> Result<Vec<SimpleGrid>, String> {
                     assert_eq!(name, "linspace");
 
                     let start = iter.next();
-                    let start: f32 = match start {
+                    let start: Float = match start {
                         Some(x) => x.parse().map_err(|e| format!("linspace: {}", e))?,
                         None => return Err(format!("")),
                     };
                     let end = iter.next();
-                    let end: f32 = match end {
+                    let end: Float = match end {
                         Some(x) => x.parse().map_err(|e| format!("linspace: {}", e))?,
                         None => return Err(format!("")),
                     };
@@ -85,10 +87,10 @@ pub fn json_to_grids(json: &str) -> Result<Vec<SimpleGrid>, String> {
                 if !x[0].is_array() {
                     let v = x
                         .members()
-                        .map(|x: &JsonValue| -> Result<f32, String> {
+                        .map(|x: &JsonValue| -> Result<Float, String> {
                             Ok(x.as_number().ok_or_else(|| format!("Array contained something that could not be converted to an array"))?.into())
                         })
-                        .collect::<Result<Vec<f32>, _>>()?;
+                        .collect::<Result<Vec<Float>, _>>()?;
                     Ok(ArrayForm::Array1(ndarray::Array::from(v)))
                 } else {
                     let arrlen2 = x[0].len();
diff --git a/sbp/tests/convergence.rs b/sbp/tests/convergence.rs
index aee9f46..1d5759b 100644
--- a/sbp/tests/convergence.rs
+++ b/sbp/tests/convergence.rs
@@ -1,8 +1,9 @@
 #![cfg(feature = "expensive_tests")]
 use ndarray::prelude::*;
 use sbp::euler::*;
+use sbp::Float;
 
-fn run_with_size<SBP: sbp::operators::UpwindOperator>(size: usize) -> f32 {
+fn run_with_size<SBP: sbp::operators::UpwindOperator>(size: usize) -> Float {
     let nx = size;
     let ny = size;
     let x = Array1::linspace(-5.0, 5.0, nx);
@@ -28,7 +29,7 @@ fn run_with_size<SBP: sbp::operators::UpwindOperator>(size: usize) -> f32 {
     sys.vortex(0.0, vortex_params);
 
     let time = 0.2;
-    let dt = 0.2 * f32::min(1.0 / (nx - 1) as f32, 1.0 / (ny - 1) as f32);
+    let dt = 0.2 * Float::min(1.0 / (nx - 1) as Float, 1.0 / (ny - 1) as Float);
 
     let nsteps = (time / dt) as usize;
     for _ in 0..nsteps {
@@ -36,15 +37,15 @@ fn run_with_size<SBP: sbp::operators::UpwindOperator>(size: usize) -> f32 {
     }
 
     let mut verifield = Field::new(ny, nx);
-    verifield.vortex(sys.x(), sys.y(), nsteps as f32 * dt, vortex_params);
+    verifield.vortex(sys.x(), sys.y(), nsteps as Float * dt, vortex_params);
 
     verifield.h2_err::<SBP>(sys.field())
 }
 
 #[test]
 fn convergence() {
-    let sizes = [25, 35, 50, 71, 100, 150];
-    let mut prev: Option<(usize, f32)> = None;
+    let sizes = [25, 35, 50, 71, 100, 150, 200];
+    let mut prev: Option<(usize, Float)> = None;
     println!("Size\tError(h2)\tq");
     for size in &sizes {
         print!("{:3}x{:3}", size, size);
@@ -57,7 +58,8 @@ fn convergence() {
             let (size1, e1) = prev;
             let m1 = size1 * size1;
 
-            let q = f32::log10(e0 / e1) / f32::log10((m0 as f32 / m1 as f32).powf(1.0 / 2.0));
+            let q =
+                Float::log10(e0 / e1) / Float::log10((m0 as Float / m1 as Float).powf(1.0 / 2.0));
             print!("\t{}", q);
         }
         println!();
diff --git a/webfront/Cargo.toml b/webfront/Cargo.toml
index 0e70c41..73a5398 100644
--- a/webfront/Cargo.toml
+++ b/webfront/Cargo.toml
@@ -12,5 +12,5 @@ path = "lib.rs"
 wasm-bindgen = "0.2.58"
 console_error_panic_hook = "0.1.6"
 wee_alloc = "0.4.5"
-sbp = { path = "../sbp" }
+sbp = { path = "../sbp", features = ["f32"] }
 ndarray = "0.13.0"