Cannot transpose a TMatrixFSparse matrix - Error in <Transpose>: matrix has wrong shape

[atha.stam]

Dear co-rooters,

I am trying to transpose a matrix constructed with TMastrixFSparse but I get the error

Error in <Transpose>: matrix has wrong shape

A simplified code to illustrate my issue can be seen below

#include "TMath.h"
#include "TMatrixF.h"
#include "TMatrixFSparse.h"

void TMatrix_Transpose(){
	TMatrixFSparse G(5, 1);
	
	int   icol[3] = {0, 0, 0};
	int   irow[3] = {1, 2, 3};
	float data[3] = {1.2, 1.3, 1.4};
	
	G.SetMatrixArray(3, irow, icol, data);
	
	G.Print();
	
	(G.T()).Print();
}

I am compiling my code using ACLiC . Any idea on what might be the issue?

Thanks in advance!

[kialbert]

It seems TMatrixFSparse can only transpose square matrices. There is an explicit check for this in the code.

If you change your definition of G to TMatrixFSparse G(5, 5); your code example will work.

As to why it is coded this way I cannot answer; The dense TMatrix can handle non-square transposes.

Cheers,
Kim

[atha.stam]

Oh I see…
This is bad…
Is there a way to transpose a non-square sparse Matrix?

[kialbert]

There is this workaround:

G.ResizeTo(5, 5);
G.T()
G.ResizeTo(1, 5);
G.Print();

Unfortunately this is the best I can give you

(I also opened a JIRA ticket for this issue, so that we may have resolution in a future release.)

Cheers,
Kim

[atha.stam]

Thank you very much for your workaround!
It’s better than nothing!