def ifft(f,gamma=0.,delta=0.,scale=1.):
from numpy import sqrt, roll, arange, exp, sign
from numpy.fft import ifft as ift
from scipy import pi
from spyctral.common.indexing import integer_range
from connection import int_connection_backward
try:
from pymbolic.algorithm import ifft
except:
from numpy.fft import ifft
N = f.size
ks = integer_range(N)
fx = int_connection_backward(f,0,0,gamma,delta)
flags = ks!=0
flags2 = ((ks%2)==1)
fx[flags2] *= -1
fx[flags] /= exp(-1j*ks[flags]*pi/N)
fx = roll(fx,-(N-1)/2)
if fx.dtype==object:
import pymbolic.algorithm as pyalg
return 1/sqrt(2*pi)*pyalg.sym_fft(fx,sign=-1)
else:
return N/float(sqrt(2*pi)*ift(fx))
def fft(fx,gamma=0,delta=0,scale=1):
from numpy import sqrt, roll, arange, exp, sign
from numpy.fft import fft as ft
from scipy import pi
from spyctral.common.indexing import integer_range
try:
from pymbolic.algorithm import fft
except:
from numpy.fft import fft
from connection import int_connection
N = fx.size
if fx.dtype==object:
import pymbolic.algorithm as pyalg
modes = pyalg.sym_fft(fx)*float(sqrt(2*pi)/N)
else:
modes = fft(fx)*sqrt(2*pi)/N
ks = integer_range(N)
modes = roll(modes,N/2)
flags = ks!=0
flags2 = ((ks%2)==1)
modes[flags] *= exp(-1j*ks[flags]*pi/N)
modes[flags2] *= -1
return int_connection(modes,0,0,gamma,delta)
def ifft_online(f,overhead):
from numpy.fft import ifft as ift
from numpy import roll
from connection import int_connection_backward_online
try:
from pymbolic.algorithm import fft
except:
from numpy.fft import fft
fx = int_connection_backward_online(f,overhead[1])
fx /= overhead[0]
N = fx.size
fx = roll(fx,-(N/2))
if fx.dtype==object:
import pymbolic.algorithm as pyalg
return pyalg.sym_fft(fx,sign=-1)/float(N)
else:
return ift(fx)
def test_fft():
numpy = pytest.importorskip("numpy")
from pymbolic import var
from pymbolic.algorithm import fft, sym_fft
vars = numpy.array([var(chr(97 + i)) for i in range(16)], dtype=object)
print(vars)
print(fft(vars))
traced_fft = sym_fft(vars)
from pymbolic.mapper.stringifier import PREC_NONE
from pymbolic.mapper.c_code import CCodeMapper
ccm = CCodeMapper()
code = [ccm(tfi, PREC_NONE) for tfi in traced_fft]
for cse_name, cse_str in enumerate(ccm.cse_name_list):
print("%s = %s" % (cse_name, cse_str))
for i, line in enumerate(code):
print("result[%d] = %s" % (i, line))
def test_fft():
numpy = pytest.importorskip("numpy")
from pymbolic import var
from pymbolic.algorithm import fft, sym_fft
vars = numpy.array([var(chr(97+i)) for i in range(16)], dtype=object)
print(vars)
print(fft(vars))
traced_fft = sym_fft(vars)
from pymbolic.mapper.stringifier import PREC_NONE
from pymbolic.mapper.c_code import CCodeMapper
ccm = CCodeMapper()
code = [ccm(tfi, PREC_NONE) for tfi in traced_fft]
for cse_name, cse_str in enumerate(ccm.cse_name_list):
print("%s = %s" % (cse_name, cse_str))
for i, line in enumerate(code):
print("result[%d] = %s" % (i, line))
