Matlab row subtraction of matrix

Matlab subtractions of rows of matrix(eg:- row2-row1) and then how to rewrite the resulatant entire matrix where 2nd row = row2 - row1

Answer 1

[Paul Hoffrichter]

On the other hand, maybe you want to subtract row 2 from all the rows. In that case, you can do this.

>> A
A =
     1     2     3     4
    11    12    13    14
    22    23    24    25
    42    43    44    45
>> AsubRow2 = A - A(2,:)
AsubRow2 =
   -10   -10   -10   -10
     0     0     0     0
    11    11    11    11
    31    31    31    31

[Paul Hoffrichter]

But if you wanted to subtract all rows from row 2, then

>> A(2,:) - A
ans =
    10    10    10    10
     0     0     0     0
   -11   -11   -11   -11
   -31   -31   -31   -31

Answer 2

[Paul Hoffrichter]

I am taking a guess as to what you want. Would be nice if you gave a simple matrix, A, and showed the desired result. But here is my guess about how to subtract adjacent rows.

>> A = [ 1 2 3 4; 11 12 13 14; 22 23 24 25; 42 43 44 45]
A =
     1     2     3     4
    11    12    13    14
    22    23    24    25
    42    43    44    45
>> Adf = diff(A)
Adf =
    10    10    10    10
    11    11    11    11
    20    20    20    20

[Virendra Kowale]

In Matlab after subtraction operation of row2 of the same matrix(eg:-row2' = row2-row1) how to rewrite the resulatant matrix where 1st row is as it is and 2nd row' = row2 - row1

A'=[row1; row2']

[Paul Hoffrichter]

A = [ 1 2 3 4; 11 12 13 14; 22 23 24 25; 42 43 44 45];
B = myFunction(A);

I am not sure what you want. row' = row2 - row1. row' on the left hand side of an = sign is incorrect. Please write down what the values in B should be for the input matrix A.