Use StdFloat to fix compile error

sbp/Cargo.toml

@@ -13,6 +13,7 @@ num-traits = "0.2.14"
 float = { path = "../utils/float" }
 constmatrix = { path = "../utils/constmatrix" }
 core_simd = { git = "https://github.com/rust-lang/portable-simd" }
+std_float = { git = "https://github.com/rust-lang/portable-simd" }
 
 [features]
 # Use f32 as precision, default is f64

sbp/src/operators/algos.rs

@@ -2,6 +2,7 @@ use super::*;
 use ndarray::s;
 use num_traits::Zero;
 use std::convert::TryInto;
+use std_float::StdFloat;
 
 pub(crate) use constmatrix::{ColVector, Matrix, RowVector};
 
@@ -442,7 +443,7 @@ pub(crate) fn diff_op_2d_sliceable_y_simd<const M: usize, const N: usize, const
                 for (iprev, &bl) in bl.iter().enumerate() {
                     f = index_to_simd(iprev).mul_add(SimdT::splat(bl), f);
                 }
-                f *= idx;
+                f *= SimdT::splat(idx);
                 fut.clone_from_slice(f.as_array());
             }
             for (j, fut) in (simdified..ny).zip(fut.into_remainder()) {
@@ -494,7 +495,7 @@ pub(crate) fn diff_op_2d_sliceable_y_simd<const M: usize, const N: usize, const
                     let offset = ifut - half_diag_width + id;
                     f = index_to_simd(offset).mul_add(SimdT::splat(d), f);
                 }
-                f *= idx;
+                f *= SimdT::splat(idx);
                 fut.clone_from_slice(f.as_array());
             }
             for (j, fut) in (simdified..ny).zip(fut.into_remainder()) {