For compiler g++ on Linux, it doesn't work if I use
int **data = new int[m][n];
Can I new an array of int* first, and new an one-dimension array for the
first int*,
then use a loop to make every int* point to the right position?
int **data = new int*[m];
data[0] = new int[m*n];
for(i = 1; i < m; i++)
data[i] = data[0] + i * n;
It should works, however, it failed in my MPI program.
Could anyone give me a better method? Thanks. 5 7985
"Wonder" <wo****@wonder. com> wrote in message news:3f******** @rutgers.edu... For compiler g++ on Linux, it doesn't work if I use
int **data = new int[m][n];
Can I new an array of int* first, and new an one-dimension array for the first int*, then use a loop to make every int* point to the right position?
int **data = new int*[m]; data[0] = new int[m*n]; for(i = 1; i < m; i++) data[i] = data[0] + i * n;
It should works, however, it failed in my MPI program. Could anyone give me a better method? Thanks.
Use pointers. C++ requires you to instantiate arrays with const values. So
instead:
int **data = (int**)malloc(m *sizeof(int*));
for (i=0;i<m;i++)
(*data+i)=(int* )malloc(n*sizeo f(int));
That would be my take. This will work, but there will probably be better
ways of doing it.
--Larry
"Wonder" <wo****@wonder. com> wrote in message news:3f******** @rutgers.edu... For compiler g++ on Linux, it doesn't work if I use
int **data = new int[m][n];
Because the type of new int[m][n] is not int**.
POINTERS ARE NOT THE SAME AS ARRAYS.
Can I new an array of int* first, and new an one-dimension array for the first int*, then use a loop to make every int* point to the right position?
int **data = new int*[m]; data[0] = new int[m*n]; for(i = 1; i < m; i++) data[i] = data[0] + i * n;
This looks like it should have worked to me. What happened?
"Larry Lindsey" <gt*****@prism. gatech.edu> wrote in message news:bk******** **@news-int.gatech.edu. ..
Use pointers. C++ requires you to instantiate arrays with const values. So instead:
He did use pointers. Why on earth are you using malloc? Your code won't
work anyhow. Presuably you meant *(data+i) or data[i] in the lhs of the
last line.
"Ron Natalie" <ro*@sensor.com > wrote in message
news:3f******** *************** @news.newshosti ng.com... "Larry Lindsey" <gt*****@prism. gatech.edu> wrote in message
news:bk******** **@news-int.gatech.edu. ..
Use pointers. C++ requires you to instantiate arrays with const values.
So instead:
He did use pointers. Why on earth are you using malloc? Your code won't work anyhow. Presuably you meant *(data+i) or data[i] in the lhs of the last line.
Oh, yeah. Good point. I'm basically a newbie anywho.
"Larry Lindsey" <gt*****@prism. gatech.edu> wrote in message
news:bk******** **@news-int.gatech.edu. .. Oh, yeah. Good point. I'm basically a newbie anywho.
So why do you purport to teach others?
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