I have this test implemented in my code, when I import a numeric matrix, which I thought would be bulletproof, but it's failing in this case:
In[]:= MatrixQ[{{}, {}}, NumericQ[#] && MatchQ[#, _Real] &]
Out[]= True
I don't get it.
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Because there are no elements in your matrix. So there is no element which is not numeric and real.
MatrixQ[{{}, {}}, False &]
returns True too.
So you have to exclude that case:
MatrixQ[##, NumericQ[#] && MatchQ[#, _Real] &] && !MatrixQ[##, False &] &
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1$\begingroup$ I'd find the example
MatrixQ[{{}, {}}, False &]somewhat more convincing. (Typo? If not, considerMatrixQ[{{1}, {1}}, True].) Or maybeMatrixQ[{{}, {}}, Print]vs.MatrixQ[{{1}, {1}}, Print]. In any case, +1. $\endgroup$ – Michael E2 Oct 15 '16 at 21:40 -
$\begingroup$ @MichaelE2 Whoops. Thanks for pointing out $\endgroup$ – meneken17 Oct 15 '16 at 21:43
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$\begingroup$ Thanks! And how can I catch this case? I have tried several things without success. $\endgroup$ – Santiago Oct 16 '16 at 9:18
