Here we will explain the parameter file entry by entry based on the final toml file for the biexponential ivim fitting.
[General]
Class = "IVIMParams" # This identifier is used in the fitting to create a matching parameters class and is the base of the file
description = "Biexponential fitting parameters for kidney data." # (optional) description of the used file
fit_type = "multi" # defines wether the fitting should use multi threating, run on a single core or utilize a gpu
n_pools = 4 # (optional) number of pools used for the multi approach
max_iter = 250 # number of iterations the solver uses to fit
b_values = [ # x-axis data
0,
10,
20,
30,
40,
50,
70,
100,
150,
200,
250,
350,
450,
550,
650,
750
]
[Model] # here are the model specific parameters descripte in more detail
model = "biexp" # the desired model to fit
fit_reduced = false # (optional) the reduced model is used to reduce the complexity of the data by assuming the data is normalized
fit_s0 = false # (optional) instead of fittig a*exp(-x_data*b) + ... S0 * (a*exp(-x_data*b) + ... ) models are used
fit_t1 = false # (optional) additional term for t1 fitting
repetition_time = 2000 # (optional) repetition time for t1 fitting
fit_t1_steam = false # (optional) wether T1 decay during Mixing Time for STEAM acquisition should be considered
mixing_time = 20 # (optional) needed for t1 fitting of steam data
[boundaries.D] # necessary boundary values for the model: f1 * exp(-b_values*D1) + f2 * exp(-b_values*D2)
1 = [0.001, 0.0007, 0.05]
2 = [0.02, 0.003, 0.3]
[boundaries.f]
1 = [85, 10, 500]
2 = [20, 1, 100]