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How can I return an array from C to python

17 New Member
Now i need information about interface c and python.Now i call c function from python but i dont know how to return a array from c to python
Mar 19 '07 #1
5 2759
bartonc
6,596 Recognized Expert Expert
Now i need information about interface c and python.Now i call c function from python but i dont know how to return a array from c to python
You'll have to remind me which tool you are using. Also, please post an example of what you are working on.
Mar 19 '07 #2
shashi59
17 New Member
#include <Python.h>
#include <Numeric/arrayobject.h>
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>

#define IDENTITY_DOC "\
This method simply unpacks the Array (so that it could be modified)\
and then returns it unchanged."
static PyObject *identity(PyObj ect *self, PyObject *args)
{
int i,n;
PyObject *input;
PyArrayObject *array;
char *aptr;

if (!PyArg_ParseTu ple(args, "O", &input ))
return NULL;
array = (PyArrayObject *) PyArray_Contigu ousFromObject(i nput, PyArray_INT, 0, 3);
if (array == NULL)
return NULL;

// Compute Size of Array
if(array->nd == 0)
n = 1;
else {
n = 1;
for(i=0;i<array->nd;i++)
n = n * array->dimensions[i];
}

aptr=(char*)(ar ray->data);

// Do Your Array Operation(s)

// Return the result
return PyArray_Return( array);
}


this is my wrapper code in c.in this code finally i was return a array (pyArray_Return (array).so how can i get the return value in python


And also i had Python2.5
Mar 19 '07 #3
shashi59
17 New Member
Now i need information about interface c and python.Now i call c function from python but i dont know how to return a array from c to python

this is my samplecode
Expand|Select|Wrap|Line Numbers
  1. #include <Python.h>
  2. #include <Numeric/arrayobject.h>
  3. #include <sys/types.h>
  4. #include <stdio.h>
  5. #include <stdlib.h>
  6.  
  7. #define IDENTITY_DOC "\
  8. This method simply unpacks the Array (so that it could be modified)\
  9. and then returns it unchanged."
  10. static PyObject *identity(PyObject *self, PyObject *args)
  11. {
  12. int i,n;
  13. PyObject *input;
  14. PyArrayObject *array;
  15. char *aptr;
  16.  
  17. if (!PyArg_ParseTuple(args, "O", &input ))
  18. return NULL;
  19. array = (PyArrayObject *) PyArray_ContiguousFromObject(input, PyArray_INT, 0, 3);
  20. if (array == NULL)
  21. return NULL;
  22.  
  23. // Compute Size of Array 
  24. if(array->nd == 0)
  25. n = 1;
  26. else {
  27. n = 1;
  28. for(i=0;i<array->nd;i++) 
  29. n = n * array->dimensions[i];
  30.  
  31. aptr=(char*)(array->data);
  32.  
  33. // Do Your Array Operation(s)
  34.  
  35. // Return the result
  36. return PyArray_Return(array);
  37. }
  38.  
  39.  
this is my wrapper code in c.in this code finally i was return a array (pyArray_Return (array).so how can i get the return value in python


And also i had Python2.5
Mar 19 '07 #4
card
10 New Member
Did you ever figure this out? I'm new to the forum, but I have the answer if you still need it.
Jun 14 '07 #5
bartonc
6,596 Recognized Expert Expert
Did you ever figure this out? I'm new to the forum, but I have the answer if you still need it.
Hello, card. Welcome to the Python Forum on TheScripts.

Please feel free to update any posts that may assist others in the future.
We appreciate any contribution and hope to be able to assist you with you queries.

Thanks for joining.
Jun 14 '07 #6

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