Perhaps the effects of the two value of parameter 'row_colume' of 'get_xs, 'outin' and 'inout', have been wrongly swapped?

Development
1

hello,everyone!
i have use pwr pin to learn the MGXS generation, but when i use

energylist = [0, 1.2e-7, 4.5e-7, 3.05902e-6, 1.30073e-4, 6.73795e-2, 20]
groups = openmc.mgxs.EnergyGroups([energy*1e6 for energy in energylist])
xs_library[uni]['ScatterMatrixXS-xs'] = openmc.mgxs.ScatterMatrixXS(energy_groups=groups)

to generate ScatterMatrix of the pin, i get result of ScatterMatrix use
xs_library[uni]['ScatterMatrixXS-xs'].get_xs(xs_type='macro', nuclides='sum')
and when i use print() in python to check the value, i get

[[3.89611656e-01 3.95605584e-02 6.71530555e-05 1.36321295e-06
  5.92701284e-08 1.18540257e-07]
 [0.00000000e+00 7.23148909e-01 5.41312527e-02 1.05400575e-03
  1.36222811e-04 4.62072781e-05]
 [0.00000000e+00 0.00000000e+00 7.03469039e-01 8.42061134e-02
  9.90423658e-03 2.72137212e-03]
 [0.00000000e+00 0.00000000e+00 2.26160868e-04 6.02446893e-01
  1.38946959e-01 3.11188793e-02]
 [0.00000000e+00 0.00000000e+00 0.00000000e+00 5.64544524e-03
  6.87163595e-01 2.13491921e-01]
 [0.00000000e+00 0.00000000e+00 0.00000000e+00 1.17367824e-06
  5.71193988e-02 1.23239619e+00]]

apparently, according to the form of the matrice, the output is that outgroup is 1st dimesion, and ingroup is 2nd dimesion
but the content of introduction of the python api says,

row_column ({‘inout’, ‘outin’}) – Return the cross section indexed first by incoming group and second by outgoing group (‘inout’), or vice versa (‘outin’). Defaults to ‘inout’.

Did I overlook any key information? Why is this happening？

2

@paulromano sorry to bother you, Paul, but I really need help :worried: