list manipulation - Multiplying columns with factor

If I have a matrix

matrix=Table[RandomInteger[],{i,3},{j,3}]

And I multiply it with

vector={1,3,5}

All three rows change accordingly.

What do I have to do, when I want to change the columns? Is this:

Transpose@matrix*vector//Transpose

the shortest solution, or do you have better ideas? Because

matrix*Transpose@vector

does not work.

Answer

This will multiply the vector by each row of matrix individually:

vector # & /@ matrix

and give the same result as

Transpose[matrix] vector // Transpose

Edit: To get rid of all the useful shorthand to see what is going on underneath, this is identical to what I wrote above:

Map[Function[Times[vector, #]], matrix]

Comments

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