added scipy fft alternative

src/scgenerator/math.py

@@ -3,6 +3,7 @@ collection of purely mathematical function
 """
 
 import math
+import platform
 import warnings
 from dataclasses import dataclass
 from functools import cache
@@ -10,6 +11,7 @@ from typing import Callable, Sequence
 
 import numba
 import numpy as np
+from scipy import fft as sfft
 from scipy.interpolate import interp1d, lagrange
 from scipy.special import jn_zeros
 
@@ -20,10 +22,16 @@ c = 299792458.0
 def fft_functions(
     full_field: bool,
 ) -> tuple[Callable[[np.ndarray], np.ndarray], Callable[[np.ndarray], np.ndarray]]:
-    if full_field:
+    if platform.processor() == "arm":
-        return np.fft.rfft, np.fft.irfft
+        if full_field:
+            return sfft.rfft, sfft.irfft
+        else:
+            return sfft.fft, sfft.ifft
     else:
-        return np.fft.fft, np.fft.ifft
+        if full_field:
+            return np.fft.rfft, np.fft.irfft
+        else:
+            return np.fft.fft, np.fft.ifft
 
 
 def expm1_int(y: np.ndarray, dx: float) -> np.ndarray:

src/scgenerator/operators.py

@@ -2,6 +2,7 @@
 This file includes Dispersion, NonLinear and Loss classes to be used in the solver
 Nothing except the solver should depend on this file
 """
+
 from __future__ import annotations
 
 from typing import Callable
@@ -268,21 +269,32 @@ def constant_wave_vector(
 ##################################################
 
 
-def envelope_raman(hr_w: np.ndarray, raman_fraction: float) -> FieldOperator:
+def envelope_raman(
+    hr_w: np.ndarray,
+    raman_fraction: float,
+    fft: Callable[[np.ndarray], np.ndarray],
+    ifft: Callable[[np.ndarray], np.ndarray],
+) -> FieldOperator:
     def operate(field: np.ndarray, z: float) -> np.ndarray:
-        return raman_fraction * np.fft.ifft(hr_w * np.fft.fft(math.abs2(field)))
+        return raman_fraction * ifft(hr_w * fft(math.abs2(field)))
 
     return operate
 
 
 def full_field_raman(
-    raman_type: str, raman_fraction: float, t: np.ndarray, w: np.ndarray, chi3: float
+    raman_type: str,
+    raman_fraction: float,
+    t: np.ndarray,
+    w: np.ndarray,
+    chi3: float,
+    fft: Callable[[np.ndarray], np.ndarray],
+    ifft: Callable[[np.ndarray], np.ndarray],
 ) -> FieldOperator:
     hr_w = fiber.delayed_raman_w(t, raman_type)
     factor_in = units.epsilon0 * chi3 * raman_fraction
 
     def operate(field: np.ndarray, z: float) -> np.ndarray:
-        return factor_in * field * np.fft.irfft(hr_w * np.fft.rfft(math.abs2(field)))
+        return factor_in * field * ifft(hr_w * fft(math.abs2(field)))
 
     return operate
 
@@ -461,14 +473,16 @@ def envelope_nonlinear_operator(
     ss_op: VariableQuantity,
     spm_op: FieldOperator,
     raman_op: FieldOperator,
+    fft: Callable[[np.ndarray], np.ndarray],
+    ifft: Callable[[np.ndarray], np.ndarray],
 ) -> SpecOperator:
     def operate(spec: np.ndarray, z: float) -> np.ndarray:
-        field = np.fft.ifft(spec)
+        field = ifft(spec)
         return (
             -1j
             * gamma_op(z)
             * (1 + ss_op(z))
-            * np.fft.fft(field * (spm_op(field, z) + raman_op(field, z)))
+            * fft(field * (spm_op(field, z) + raman_op(field, z)))
         )
 
     return operate
@@ -480,10 +494,12 @@ def full_field_nonlinear_operator(
     spm_op: FieldOperator,
     plasma_op: FieldOperator,
     fullfield_nl_prefactor: VariableQuantity,
+    fft: Callable[[np.ndarray], np.ndarray],
+    ifft: Callable[[np.ndarray], np.ndarray],
 ) -> SpecOperator:
     def operate(spec: np.ndarray, z: float) -> np.ndarray:
-        field = np.fft.irfft(spec)
+        field = ifft(spec)
         total_nonlinear = spm_op(field) + raman_op(field) + plasma_op(field)
-        return 1j * fullfield_nl_prefactor(z) * np.fft.rfft(total_nonlinear)
+        return 1j * fullfield_nl_prefactor(z) * fft(total_nonlinear)
 
     return operate

src/scgenerator/spectra.py

@@ -8,6 +8,7 @@ from pathlib import Path
 from typing import Callable, Generic, Iterator, Sequence, TypeVar, overload
 
 import numpy as np
+import scipy.fft as sfft
 import scipy.signal as ss
 from tqdm import tqdm
 
@@ -48,7 +49,12 @@ class Spectrum(np.ndarray):
         if buf[:2] != b"S\xc9":
             raise OSError("not a valid buffer")
         buf = buf[2:]
-        ifft = np.fft.ifft if buf[:4] == b"comp" else np.fft.irfft
+        ifft = {
+            b"comp": np.fft.ifft,
+            b"real": np.fft.irfft,
+            b"scic": sfft.ifft,
+            b"scir": sfft.irfft,
+        }
         shape_n = buf[4]
         nt, *shape = (
             int.from_bytes(buf[5 + i * 8 : 5 + (i + 1) * 8], "big") for i in range(shape_n)
@@ -122,6 +128,10 @@ class Spectrum(np.ndarray):
             f_name = b"comp"
         elif self.ifft is np.fft.irfft:
             f_name = b"real"
+        elif self.ifft is sfft.ifft:
+            f_name = b"scic"
+        elif self.ifft is sfft.irfft:
+            f_name = b"scir"
         else:
             raise ValueError(f"cannot export ifft function {self.ifft!r}")
 
@@ -298,12 +308,10 @@ class Propagation(Generic[ParamsOrNone]):
         return self._current_index
 
     @overload
-    def __getitem__(self: Propagation[Parameters], key: int | slice) -> Spectrum:
+    def __getitem__(self: Propagation[Parameters], key: int | slice) -> Spectrum: ...
-        ...
 
     @overload
-    def __getitem__(self: Propagation[None], key: int | slice) -> np.ndarray:
+    def __getitem__(self: Propagation[None], key: int | slice) -> np.ndarray: ...
-        ...
 
     def __getitem__(self, key: int | slice) -> Spectrum | np.ndarray:
         if isinstance(key, slice):
@@ -326,12 +334,10 @@ class Propagation(Generic[ParamsOrNone]):
             return array
 
     @overload
-    def _load_slice(self: Propagation[Parameters], key: slice) -> Spectrum:
+    def _load_slice(self: Propagation[Parameters], key: slice) -> Spectrum: ...
-        ...
 
     @overload
-    def _load_slice(self: Propagation[None], key: slice) -> np.ndarray:
+    def _load_slice(self: Propagation[None], key: slice) -> np.ndarray: ...
-        ...
 
     def _load_slice(self, key: slice) -> Spectrum:
         self._warn_negative_index(key.start)
@@ -412,12 +418,10 @@ class PropagationCollection:
     wl: np.ndarray
 
     @overload
-    def __getitem__(self, key: int) -> Propagation:
+    def __getitem__(self, key: int) -> Propagation: ...
-        ...
 
     @overload
-    def __getitem__(self, key: slice) -> list[Propagation]:
+    def __getitem__(self, key: slice) -> list[Propagation]: ...
-        ...
 
     def __getitem__(self, key: int | slice) -> Propagation | list[Propagation]:
         return self.propagations[key]