import math
import warnings
import numpy as np
from matplotlib import pyplot as plt
import pypulseq as pp
# ======
# SETUP
# ======
dG = 250e-6
# Set system limits
system = pp.Opts(max_grad=32, grad_unit='mT/m', max_slew=130, slew_unit='T/m/s', rf_ringdown_time=100e-6,
rf_dead_time=100e-6, adc_dead_time=10e-6)
seq = pp.Sequence(system) # Create a new sequence object
# Define FOV and resolution
fov = 256e-3
Nx, Ny = 128, 128
n_echo = 16
n_slices = 1
rf_flip = 180
if isinstance(rf_flip, int):
rf_flip = np.zeros(n_echo) + rf_flip
slice_thickness = 5e-3
TE = 12e-3
TR = 2000e-3
TE_eff = 60e-3
k0 = round(TE_eff / TE)
Nx = 256
Ny = 256
alpha = 90 # flip angle
slice_thickness = 3e-3 # slice
TE = np.array([4.3e-3])
TR = 300e-3
rf_spoiling_inc = 117 # RF spoiling increment
ext_pulse_library = 1 # 0 - pypulseq, 1 - sigpy
ext_pulse_type = 'slr'
disp_pulse = 0
system = pp.Opts(max_grad=28,
grad_unit='mT/m',
max_slew=150,
slew_unit='T/m/s',
rf_ringdown_time=20e-6,
rf_dead_time=100e-6,
adc_dead_time=10e-6,
rf_raster_time=1e-6)
# Common pulse design parameters
duration = 3e-3 # seconds
tb = 4
# ======
# CREATE EVENTS
# ======
if (ext_pulse_library):
# Declare pulse configuration inputs here
pulse_freq_offset = 0.0 # if designing rf pulse without a FM
if ext_pulse_type == 'slr':