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#!/usr/bin/env python
#
# Copyright 2004 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# SPDX-License-Identifier: GPL-3.0-or-later
#
#
import math
import sys
def gen_approx_table(f, nentries, min_x, max_x):
"""return a list of nentries containing tuples of the form:
(m, c). min_x and max_x specify the domain
of the table.
"""
r = []
incx = float(max_x - min_x) / nentries
for i in range(nentries):
a = (i * incx) + min_x
b = ((i + 1) * incx) + min_x
m = (f(b) - f(a)) / (b - a)
c = f(a)
r.append((m, c))
return r
def scaled_sine(x):
return math.sin(x * math.pi / 2**31)
def gen_sine_table():
nbits = 10
nentries = 2**nbits
# min_x = -2**31
# max_x = 2**31-1
min_x = 0
max_x = 2**32 - 1
t = gen_approx_table(scaled_sine, nentries, min_x, max_x)
# sys.stdout.write ('static const int WORDBITS = 32;\n')
# sys.stdout.write ('static const int NBITS = %d;\n' % (nbits,))
# sys.stdout.write ('static const double sine_table[%d][2] = {\n'% (nentries,))
for e in t:
sys.stdout.write(' { %22.15e, %22.15e },\n' % (e[0], e[1]))
# sys.stdout.write ('};\n')
if __name__ == '__main__':
gen_sine_table()
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