Finishing up freq meas

controller/fw/tools/fft_window_header_gen.py

@@ -0,0 +1,59 @@
+#!/usr/bin/env python3
+
+import textwrap
+
+import scipy.signal as sig
+import numpy as np
+
+WINDOW_TYPES = [
+        'boxcar',
+        'triang',
+        'blackman',
+        'hamming',
+        'hann',
+        'bartlett',
+        'flattop',
+        'parzen',
+        'bohman',
+        'blackmanharris',
+        'nuttall',
+        'barthann',
+        'kaiser',
+        'gaussian',
+        'general_gaussian',
+        'slepian',
+        'dpss',
+        'chebwin',
+        'exponential',
+        'tukey',
+        ]
+
+if __name__ == '__main__':
+    import argparse
+    parser = argparse.ArgumentParser()
+    parser.add_argument('window', choices=WINDOW_TYPES, help='Type of window function to use')
+    parser.add_argument('n', type=int, help='Width of window in samples')
+    parser.add_argument('window_args', nargs='*', type=float,
+            help='''Window argument(s) if required. See https://docs.scipy.org/doc/scipy/reference/generated/scipy.signal.get_window.html#scipy.signal.get_window for details.''')
+    parser.add_argument('-v', '--variable', default='fft_window_table', help='Name for alias variable pointing to generated window')
+    args = parser.parse_args()
+    
+    print(f'/* FTT window table for {args.n} sample {args.window} window.')
+    if args.window_args:
+        print(f' * Window arguments were: ({" ,".join(str(arg) for arg in args.window_args)})')
+    print(f' */')
+    winargs = ''.join(f'_{arg:.4g}'.replace('.', 'F') for arg in args.window_args)
+    varname = f'fft_{args.n}_window_{args.window}{winargs}'
+    print(f'const float {varname}[{args.n}] = {{')
+
+    win = sig.get_window(args.window if not args.window_args else (args.window, *args.window_args),
+            Nx=args.n, fftbins=True)
+    par = ' '.join(f'{f:>013.8g},' for f in win)
+    print(textwrap.fill(par,
+        initial_indent=' '*4, subsequent_indent=' '*4,
+        width=120,
+        replace_whitespace=False, drop_whitespace=False))
+    print('};')
+    print()
+    print(f'const float * const {args.variable} __attribute__((weak)) = {varname};')
+