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Update slr.py #144

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Update slr.py #144

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14 changes: 7 additions & 7 deletions sigpy/mri/rf/slr.py
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Original file line number Diff line number Diff line change
Expand Up @@ -135,7 +135,7 @@ def dzls(n=64, tb=4, d1=0.01, d2=0.01):
m = [1, 1, 0, 0]
w = [1, d1 / d2]

h = signal.firls(n + 1, f, m, w)
h = signal.firls(n + 1, f, m, weight=w)
# shift the filter half a sample to make it symmetric, like in MATLAB
c = np.exp(
1j
Expand Down Expand Up @@ -253,8 +253,8 @@ def dz_gslider_b(
m_sub = [1, 1, 0, 0, 0, 0]
w = [1, 1, d1 / d2]

b_notch = signal.firls(n + 1, f, m_notch, w) # the notched filter
b_sub = signal.firls(n + 1, f, m_sub, w) # the subslice filter
b_notch = signal.firls(n + 1, f, m_notch, weight=w) # the notched filter
b_sub = signal.firls(n + 1, f, m_sub, weight=w) # the subslice filter
# add them with the subslice phase
b = np.add(b_notch, np.multiply(np.exp(1j * phi), b_sub))
# shift the filter half a sample to make it symmetric,
Expand Down Expand Up @@ -344,15 +344,15 @@ def dz_gslider_b(
)
)

b_notch = signal.firls(n + 1, f, m_notch, w) # the notched filter
b_notch = signal.firls(n + 1, f, m_notch, weight=w) # the notched filter
b_notch = sp.ifft(
np.multiply(sp.fft(b_notch, center=False), c), center=False
)
b_notch = np.real(b_notch[:n])
# hilbert transform to suppress negative passband
b_notch = signal.hilbert(b_notch)

b_sub = signal.firls(n + 1, f, m_sub, w) # the sub-band filter
b_sub = signal.firls(n + 1, f, m_sub, weight=w) # the sub-band filter
b_sub = sp.ifft(
np.multiply(sp.fft(b_sub, center=False), c), center=False
)
Expand Down Expand Up @@ -460,8 +460,8 @@ def dz_hadamard_b(n=128, g=5, gind=1, tb=4, d1=0.01, d2=0.01, shift=32):
[np.arange(0, n / 2 + 1, 1), np.arange(-n / 2, 0, 1)]
)
)
bp = signal.firls(n + 1, f, mp, w) # the positive filter
bn = signal.firls(n + 1, f, mn, w) # the negative filter
bp = signal.firls(n + 1, f, mp, weight=w) # the positive filter
bn = signal.firls(n + 1, f, mn, weight=w) # the negative filter

# combine the filters and demodulate
b = sp.ifft(
Expand Down