def iadctmatrix(N):
from iameshgrid import iameshgrid
x, u = iameshgrid(range(N), range(N)) # (u,x)
alpha = ones((N, N)) * sqrt(2. / N)
alpha[0, :] = sqrt(1. / N) # alpha(u,x)
A = alpha * cos((2 * x + 1) * u * pi / (2. * N)) # Cn(u,x)
return A
def iadctmatrix(N):
from iameshgrid import iameshgrid
x, u = iameshgrid(range(N), range(N)) # (u,x)
alpha = ones((N,N)) * sqrt(2./N)
alpha[0,:] = sqrt(1./N) # alpha(u,x)
A = alpha * cos((2*x+1)*u*pi / (2.*N)) # Cn(u,x)
return A
def iahaarmatrix(N):
from iameshgrid import iameshgrid
n = floor(log(N)/log(2))
if 2**n != N:
raise Exception, 'error: size '+str(N)+' is not multiple of power of 2'
z, k = iameshgrid(1.*arange(N)/N, 1.*arange(N))
p = floor(log(maximum(1,k))/log(2))
q = k - (2**p) + 1
z1 = (q-1) / (2**p)
z2 = (q-0.5) / (2**p)
z3 = q / (2**p)
A = (1/sqrt(N)) * ((( 2**(p/2.)) * ((z >= z1) & (z < z2))) \
+ ((-2**(p/2.)) * ((z >= z2) & (z < z3))))
A[0,:] = 1/sqrt(N)
return A
def iahadamardmatrix(N):
from iameshgrid import iameshgrid
def bitsum(x):
s = 0 * x
while x.any():
s += x & 1
x >>= 1
return s
n = floor(log(N)/log(2))
if 2**n != N:
raise Exception, 'error: size '+str(N)+' is not multiple of power of 2'
u, x = iameshgrid(range(N), range(N))
A = ((-1)**(bitsum(x & u)))/sqrt(N)
return A
def iahadamardmatrix(N):
from iameshgrid import iameshgrid
def bitsum(x):
s = 0 * x
while x.any():
s += x & 1
x >>= 1
return s
n = floor(log(N) / log(2))
if 2**n != N:
raise Exception, 'error: size ' + str(
N) + ' is not multiple of power of 2'
u, x = iameshgrid(range(N), range(N))
A = ((-1)**(bitsum(x & u))) / sqrt(N)
return A
