How to Access upper triangular Matrix elements

[suresh4ind]

Hi
i need to copy the upper triangular elements of matrix A[100][100] to an array
B[5050],how to perform this ,can u send me the accessing formula

[tnga]

Hi
i need to copy the upper triangular elements of matrix A[100][100] to an array
B[5050],how to perform this ,can u send me the accessing formula

You mean the up-right corner? So that's half the matrix...
All you have to do is to read the lines of the matrix and everytime you read a line, start reading the next line one columm to the right. All you have to do is to write the values in array B in sequence. Did I understand correctly?

Regards

[suresh4ind]

i need the mathematical formula for accessing the elements of upper triangular elements to an lineary array

[suresh4ind]

i think now the question will be more clear
see we have access formula for elements in a matrix A[i][j] to an array[index]
using row major is
index=i*(no of columns)+j
similarily i want the mathematical formula for accessing the upper triangular elements in to an array using row major

[tnga]

i think now the question will be more clear
see we have access formula for elements in a matrix A[i][j] to an array[index]
using row major is
index=i*(no of columns)+j
similarily i want the mathematical formula for accessing the upper triangular elements in to an array using row major

Yes, that's what i understood after your reply...
I guess there must be something like dividing and using the rest of divisions between the position you want to get (index on B) and the length of the lines in the matrix...
I know it's wrong, but i guess it's something like this:

B[index]=a[index%n][i-index%n]

using a nxn size matrix.

Sorry, I can't help you very much on this. Just guessing...

[suresh4ind]

hi thankx i got the answer

[tnga]

hi thankx i got the answer

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