Apply suggestions from code review

Co-authored-by: Axel Huebl <[email protected]>

Author: cemitch99

src/elements/Quad.H

@@ -340,8 +340,7 @@ namespace impactx::elements
             amrex::ParticleReal const omega = std::sqrt(std::abs(m_k));
 
             // compute trigonometric quantities
-            amrex::ParticleReal const sin_omega_ds = std::sin(omega*slice_ds);
-            amrex::ParticleReal const cos_omega_ds = std::cos(omega*slice_ds);
+            auto const [sin_omega_ds, cos_omega_ds] = amrex::Math::sincos(omega*slice_ds);
             amrex::ParticleReal const sinh_omega_ds = std::sinh(omega*slice_ds);
             amrex::ParticleReal const cosh_omega_ds = std::cosh(omega*slice_ds);
 

src/elements/mixin/spintransport.H

@@ -18,6 +18,9 @@
 #include <AMReX_Extension.H>
 #include <AMReX_REAL.H>
 
+#include <cmath>
+
+
 namespace impactx::elements::mixin
 {
     /** This is a helper class for applying a spin map generated by a three-component vector
@@ -35,22 +38,22 @@ namespace impactx::elements::mixin
          * @param[inout] sy spin vector y-component
          * @param[inout] sz spin vector z-component
          */
-        template<typename T_Real>
+        template<typename T_Real=amrex::ParticleReal>
         AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
         void rotate_spin (
-            amrex::ParticleReal lambdax,
-            amrex::ParticleReal lambday,
-            amrex::ParticleReal lambdaz,
-            amrex::ParticleReal sx,
-            amrex::ParticleReal sy,
-            amrex::ParticleReal sz
+            T_Real lambdax,
+            T_Real lambday,
+            T_Real lambdaz,
+            T_Real & AMREX_RESTRICT sx,
+            T_Real & AMREX_RESTRICT sy,
+            T_Real & AMREX_RESTRICT sz
         ) const
         {
             using namespace amrex::literals;  // for _prt
 
             // Compute quaternion coefficients
             amrex::ParticleReal angle = std::sqrt(lambdax*lambdax+lambday*lambday+lambdaz*lambdaz);
-            auto const [sin_half_angle, cos_half_angle] = amrex::Math::sincos(angle/2_prt);
+            auto const [sin_half_angle, cos_half_angle] = amrex::Math::sincos(angle*0.5_prt);
             amrex::ParticleReal w0 = cos_half_angle;
             amrex::ParticleReal w1 = (angle==0_prt) ? 0_prt : -(lambdax/angle)*sin_half_angle;
             amrex::ParticleReal w2 = (angle==0_prt) ? 0_prt : -(lambday/angle)*sin_half_angle;