How to get the result of a multiplication between a matrix and a scalar?

Question

I have a matrix,

  P = {{1, 2, 4}, {3, 4, 1}, {2, 1, 6}}
  ff=6

How to do the multiplication of ff with P? ff.P and ff*P are not working!

Can you elaborate what you mean by "not working"? ff*P returns {{6, 12, 24}, {18, 24, 6}, {12, 6, 36}} for me, as expected — Lukas Lang, May 19 '21 at 07:45
Did you use MatrixForm in the definition of your matrix? If yes, then don't. — Roman, May 19 '21 at 08:32

score 3 · Accepted Answer · answered May 19 '21 at 07:45

The ff.P does not work because it is a matrix multiplication and clearly ff is not such object.

On the other hand, ff*P and P*ff should work and they do for me.

Note that you can also write ff P and P ff. Be careful to leave a proper space between them.

The following worked for me as I said already

 $Version
"12.0.0 for Linux x86 (64-bit) (April 7, 2019)"
P = {{1, 2, 4}, {3, 4, 1}, {2, 1, 6}};
ff = 6;

And now

P*ff // MatrixForm
ff*P // MatrixForm

Both of the above expressions result in

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