How to call more than 1 pointer in a c function?

[aljon]

WELL, I'm pretty new to C, my program needed to have a function that will transpose or multiply matrices.. since a matrix (or array) of m x n, has a transposed matrix of n x m .. i would need to call 2 arrays/pointers into the Transpose function.. 1 with the original values and the other with the n by m size the array/pointer that i will put something from the original .. So how can the function know which function should be this or this ..

for example,where A[i][j] is the orig. function

for(i=0; i<column; i++)
{
  for(j=0; j<row; j++)
{
 
  B[i][j]=A[j][i];
}
}

[weaknessforcats]

The function argument names are used by the function. Just make sure your arguments are in the same order as the calling values.

[aljon]

So you mean if i write for example Function(A,B,row,col) to call it.. then it would simply mean that the function would know that since A comes first it would be the original function as it is stated inside the function?

Should i allocate a 2d pointer so that i may call the arrays/pointers into the function? The run error says that," assignmeent of read-only location" what's that supposed to mean? thanks a lot.

[vijay6]

Hey aljon, for Transpose of a matrix you can use this code.

...
 

Note: 'm not tested this code. If you have any error while executing this code, post the error message here.

[weaknessforcats]

Most likely your error is an attempt to use a memory location that does not belong to your program. Often this is caused by using an uninitiaized pointer.

I would allocate the two arrays and then call the function with the two pointers plus the rows and columns.

From inside the function it's not obvious that the function should allocate the second array. If it does allocate the second array and return the address to the calling function then it is not obvious to the calling function that the second array needs to be freed.

The general rule is "he who allocates is he who frees".

[vijay6]

Hey weaknessforcats, I don't have 'C' compiler, that's why i posted the code without testing. But 'm sure that code won't give/show errors.

[r035198x]

@Vijay6
You should not be trying to spoonfeed people anyway. Better point them in the right direction by explaining where their problem is.

[vijay6]

Hey @r035198x, i gave the answer because he said "I'm pretty new to C".