Display problem multiplying matrix

Question

I'm multiplying matrices and I don't get answer I want I just get matrix M times matrix N, there is no result. What to do and what to fix in order to get result displayed?

M = {{1, 3, 3}, {3, 4, 4}, {5, 5, 5}} // MatrixForm

P = {{1, 2, 6}, {3, 6, 4}, {5, 9, 5}} // MatrixForm

M.P

You need to include more detail of what you are doing. Possibly using Dot (short form .) will solve your problem if you have actual matrix data. The data might potentially need to be transposed. Also you can/should not use N as a variable as it is already a defined System function. — Mr.Wizard, Oct 23 '14 at 20:11
@VladimirS, This is not a good way to share your code, see the edits I did for you. — rhermans, Oct 23 '14 at 20:23
Oh, sorry. Thanks, I'll learn how to do that for my next question. — VlS, Oct 23 '14 at 20:24
The problem is MatrixForm. See, detail is important. :-) I am closing this question as a duplicate. (A link will be inserted at the top of your post.) See the answers there fore a full explanation. — Mr.Wizard, Oct 23 '14 at 20:28
Please consider taking the tour so you learn the basics of the site. Read how to do the formatting of you code here — rhermans, Oct 23 '14 at 20:30

score 2 · Answer 1 · answered Oct 23 '14 at 20:24

M = {{1, 3, 3}, {3, 4, 4}, {5, 5, 5}}

{{1, 3, 3}, {3, 4, 4}, {5, 5, 5}}

P = {{1, 2, 6}, {3, 6, 4}, {5, 9, 5}}

{{1, 2, 6}, {3, 6, 4}, {5, 9, 5}}

M.P

{{25, 47, 33}, {35, 66, 54}, {45, 85, 75}}

Or, if you want the nice display be sure not to include that in the definition of your matrix

MatrixForm[M = {{1, 3, 3}, {3, 4, 4}, {5, 5, 5}}]

Display problem multiplying matrix

1 Answers1