Add a libm and libm-force feature to transitively enable the corresponding simba feature.

Cargo.toml

@@ -31,6 +31,9 @@ debug = [ "approx/num-complex", "rand/std" ]
 alloc = [ ]
 io = [ "pest", "pest_derive" ]
 compare = [ "matrixcompare-core" ]
+libm = [ "simba/libm" ]
+libm-force = [ "simba/libm_force" ]
+
 
 [dependencies]
 typenum        = "1.11"
@@ -75,6 +78,3 @@ path = "benches/lib.rs"
 
 [profile.bench]
 lto = true
-
-#[patch.crates-io]
-#simba = { path = "../simba" }

src/linalg/mod.rs

@@ -5,6 +5,10 @@ mod bidiagonal;
 mod cholesky;
 mod convolution;
 mod determinant;
+// FIXME: this should not be needed. However, the exp uses
+// explicit float operations on `f32` and `f64`. We need to
+// get rid of these to allow exp to be used on a no-std context.
+#[cfg(feature = "std")]
 mod exp;
 mod full_piv_lu;
 pub mod givens;
@@ -27,6 +31,7 @@ mod symmetric_tridiagonal;
 pub use self::bidiagonal::*;
 pub use self::cholesky::*;
 pub use self::convolution::*;
+#[cfg(feature = "std")]
 pub use self::exp::*;
 pub use self::full_piv_lu::*;
 pub use self::hessenberg::*;