# How do I create a square matrix based on user input?

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Erin on 21 Feb 2014
Commented: Peram Balakrishna on 25 Sep 2021 at 17:26
I'm trying to write a program that asks the user what the dimensions of their square matrix are then takes that number, asks for each entry and creates the matrix for the program to use for the rest of the questions. I know how to create one row at a time, but I can't figure out how to put all the rows together to make one matrix.
Akash h.r on 16 Aug 2016
m=input('row')
n=input('column')
for i=1:m
for j=1:n
a(i,j)=input('elements-')
end
end
a=reshape(a,m,n)

Azzi Abdelmalek on 21 Feb 2014
M=[row1;row2;row3]
Erin on 21 Feb 2014
But how do I write a program that reads a matrix that I prompt someone to enter? I'm pretty sure I have to do it one component at a time, I just can't figure out how to put them in the right places. My code looks like this:
C=input('How many columns are there in P? ');
R=input('How many rows are there in P? ');
P=zeros(R:C);
co=1;
ro=1;
while co<=C && ro<=R;
if co==1
P(co)=input('What is the first value of this column of P? ')
co=co+1;
elseif co>1
P(co)=input('What is the next value of this column of P? ')
co=co+1;
end
ro=ro+1;
end
P=P(R:C)
and the output looks like:
How many columns are there in P? 2
How many rows are there in P? 2
What is the first value of this row of P? .2
P =
0.2000 0
0 0
What is the next value of this row of P? .2
P =
0.2000 0
0.2000 0
P =
0.2000

Anuj on 21 Feb 2014
One simple way for this can be, Suppose you have square matrix of order n. So you have n^2 elements. You can enter all the elements one by one and change it into square matrix like this-
n=input('order of your square matrix is? ')
for i=1:n^2;
a(i)=input('elements-');
end
a=reshape(a,n,n)'
Regards

Akash h.r on 16 Aug 2016
m=input('row')
n=input('column')
for i=1:m
for j=1:n
a(i,j)=input('elements-')
end
end
a=reshape(a,m,n)

unknown nobody on 15 Aug 2017
a = input('enter the matrix');
[1 2; 3 4]
Peram Balakrishna on 25 Sep 2021 at 17:26
simple

Bhupendra Raj Acharya on 6 Feb 2020
m=input('row')
n=input('column')
for i=1:m
for j=1:n
a(i,j)=input('elements-')
end
end
a=reshape(a,m,n)
##### 2 CommentsShowHide 1 older comment
Walter Roberson on 5 Dec 2020
The above code is valid in the command window -- though I would recommend putting in extra spaces,
m=input('row ')
n=input('column ')
for i=1:m
for j=1:n
a(i,j)=input('elements- ')
end
end
a=reshape(a,m,n)

Amjad Alotaibi on 19 Feb 2020
m=input('row')
n=input('column')
for i=1:m
for j=1:n
a(i,j)=input('elements-')
end
end
a=reshape(a,m,n)
##### 2 CommentsShowHide 1 older comment
Walter Roberson on 18 Jan 2021

Lam Nguyen Van on 24 Mar 2020
help me. I want to input symbols matrix. ex: [a b c; f a h]
Mehedi Hasan on 9 Sep 2020
How to take matrix from user. Calculate the mean, variance, covariance and standard
deviation for that matrix. Draw the histogram graph.