Thank you My problem is that I can get the matrix value in Python, but I can't get it in Golang. I suspect that the value I get must be a variable of type double. Python supports double, but Golang has no double, only float64. So ask the technical person who developed this interface to see if they can get the matrix value for a variable of type Float64.
"Mathcad Prime Objects": https://support.ptc.com/help/mathcad/r7.0/en/index.html#page/PTC_Mathcad_Help/Object_Matrix.html
Use the matrix data type instead of a 2D array to represent matrix data because the matrix data type stores rows or columns of real or complex scalar data for matrix operations, particularly some linear algebra operations. The Mathematics VIs that perform matrix operations accept the matrix data type and return matrix results, which enables subsequent polymorphic VIs and functions in the data flow to perform matrix-specific operations.