Count from MatrixForm in mathematica

  • Context: Mathematica 
  • Thread starter Thread starter 76Ahmad
  • Start date Start date
  • Tags Tags
    Count Mathematica
Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
2 replies · 3K views
76Ahmad
Messages
46
Reaction score
0
Count from "MatrixForm" in mathematica!

Hi every one, I really need help on this task..

how do I Count only the zeros elements from a MatrixForm in MATHEMATICA

Suppose I have a Matrix 100X100 full with numbers and
I just need to know how many zero is there on this matrix

thanks
 
Physics news on Phys.org


First, all the various "Form"s are wrappers that turn an ordinary simple Mathematica value into something for display and aren't usually for further processing.

So, if you have your matrix before you put it into MatrixForm then you can do this

In[1]:= m=Table[RandomInteger[{5},{5}]

Out[1]= {{1,0,1,1,1},{0,1,1,0,0},{1,0,0,1,0},{0,0,0,0,0},{1,0,1,1,0}}

In[2]:= Count[Flatten[m],0]

Out[2]= 14

and that has successfully counted the zeros in the matrix.

But

In[4]:= Count[MatrixForm[m],0]

Out[4]= 0

In[5]:= Count[Flatten[MatrixForm[m]],0]

Out[5]= 0

So if you want to see a pretty desktop published version of your matrix... use MatrixForm, but if you want to get any work done on your matrix then do not use MatrixForm.