Can you convert c++ to python

I have been trying to import a C code in python file. But its not working. So I've decided to convert the C program into Python so that importing the function will be easier. The C code I want to convert is given below. (I got this from github)

#include "Python.h"
#include "numpy/arrayobject.h"
#include <math.h>

# define CUBE(x)   ((x) * (x) * (x))
# define SQR(x)    ((x) * (x))

static PyObject *interp3_tricubic(PyObject *self, PyObject *args);  
float TriCubic (float px, float py, float pz, float *volume, int xDim, int yDim, int zDim);

// what function are exported
static PyMethodDef tricubicmethods[] = {
    {"_interp3_tricubic", interp3_tricubic, METH_VARARGS},
    {NULL, NULL}
};

// This function is essential for an extension for Numpy created in C
void inittricubic() {
    (void) Py_InitModule("tricubic", tricubicmethods);
    import_array();
}

// the data should be FLOAT32 and should be ensured in the wrapper 
static PyObject *interp3_tricubic(PyObject *self, PyObject *args) 
{
    PyArrayObject *volume, *result, *C, *R, *S;
    float *pr, *pc, *ps;
        float *pvol, *pvc;
        int xdim, ydim, zdim;

    // We expect 4 arguments of the PyArray_Type
    if(!PyArg_ParseTuple(args, "O!O!O!O!", 
                &PyArray_Type, &volume,
                &PyArray_Type, &C,
                &PyArray_Type, &R,
                &PyArray_Type, &S)) return NULL;

    if ( NULL == volume ) return NULL;
    if ( NULL == C ) return NULL;
    if ( NULL == R ) return NULL;
    if ( NULL == S ) return NULL;

    // result matrix is the same size as C and is float
    result = (PyArrayObject*) PyArray_ZEROS(PyArray_NDIM(C), C->dimensions, NPY_FLOAT, 0); 
    // This is for reference counting ( I think )
    PyArray_FLAGS(result) |= NPY_OWNDATA; 

    // massive use of iterators to progress through the data
    PyArrayIterObject *itr_v, *itr_r, *itr_c, *itr_s;
        itr_v = (PyArrayIterObject *) PyArray_IterNew(result);
        itr_r = (PyArrayIterObject *) PyArray_IterNew(R);
        itr_c = (PyArrayIterObject *) PyArray_IterNew(C);
        itr_s = (PyArrayIterObject *) PyArray_IterNew(S);
        pvol = (float *)PyArray_DATA(volume);
        xdim = PyArray_DIM(volume, 0);
        ydim = PyArray_DIM(volume, 1);
    zdim = PyArray_DIM(volume, 2);
        while(PyArray_ITER_NOTDONE(itr_v)) {
        pvc = (float *) PyArray_ITER_DATA(itr_v);
        pr = (float *) PyArray_ITE R_DATA(itr_r);
        pc = (float *) PyArray_ITER_DATA(itr_c);
        ps = (float *) PyArray_ITER_DATA(itr_s);
        *pvc = TriCubic(*pc, *pr, *ps, pvol, xdim, ydim, zdim); 
        PyArray_ITER_NEXT(itr_v);
        PyArray_ITER_NEXT(itr_r);
        PyArray_ITER_NEXT(itr_c);
        PyArray_ITER_NEXT(itr_s);
    }

    return result;
}
        
/*
 * TriCubic - tri-cubic interpolation at point, p.
 *   inputs:
 *     px, py, pz - the interpolation point.
 *     volume - a pointer to the float volume data, stored in x,
 *              y, then z order (x index increasing fastest).
 *     xDim, yDim, zDim - dimensions of the array of volume data.
 *   returns:
 *     the interpolated value at p.
 *   note:
 *     rudimentary range checking is done in this function.
 */

float TriCubic (float px, float py, float pz, float *volume, int xDim, int yDim, int zDim)
{
  int             x, y, z;
  int    i, j, k;
  float           dx, dy, dz;
  float *pv;
  float           u[4], v[4], w[4];
  float           r[4], q[4];
  float           vox = 0;
  int             xyDim;

  xyDim = xDim * yDim;

  x = (int) px, y = (int) py, z = (int) pz;
  // necessary evil truncating at dim-2 because tricubic needs 2 more values
  // which is criminal near edges
  // future work includes doing trilinear for edge cases
  // range checking is extremely important here
  if (x < 3 || x > xDim-3 || y < 3 || y > yDim-3 || z < 3 || z > zDim-3) 
    return (0);

  dx = px - (float) x, dy = py - (float) y, dz = pz - (float) z;
  pv = volume + (x - 1) + (y - 1) * xDim + (z - 1) * xyDim;

  /* factors for Catmull-Rom interpolation */

  u[0] = -0.5 * CUBE (dx) + SQR (dx) - 0.5 * dx;
  u[1] = 1.5 * CUBE (dx) - 2.5 * SQR (dx) + 1;
  u[2] = -1.5 * CUBE (dx) + 2 * SQR (dx) + 0.5 * dx;
  u[3] = 0.5 * CUBE (dx) - 0.5 * SQR (dx);

  v[0] = -0.5 * CUBE (dy) + SQR (dy) - 0.5 * dy;
  v[1] = 1.5 * CUBE (dy) - 2.5 * SQR (dy) + 1;
  v[2] = -1.5 * CUBE (dy) + 2 * SQR (dy) + 0.5 * dy;
  v[3] = 0.5 * CUBE (dy) - 0.5 * SQR (dy);

  w[0] = -0.5 * CUBE (dz) + SQR (dz) - 0.5 * dz;
  w[1] = 1.5 * CUBE (dz) - 2.5 * SQR (dz) + 1;
  w[2] = -1.5 * CUBE (dz) + 2 * SQR (dz) + 0.5 * dz;
  w[3] = 0.5 * CUBE (dz) - 0.5 * SQR (dz);

  for (k = 0; k < 4; k++)
  {
    q[k] = 0;
    for (j = 0; j < 4; j++)
    {
      r[j] = 0;
      for (i = 0; i < 4; i++)
      {
        r[j] += u[i] * *pv;
        pv++;
      }
      q[k] += v[j] * r[j];
      pv += xDim - 4;
    }
    vox += w[k] * q[k];
    pv += xyDim - 4 * xDim;
  }
  return vox;
}

I have tried to convert this code to python. But the output I got is wrong. The python code I created is added below.

    import numpy as N
    import math
    import scipy
    global result

def interp3_tricubic(volume, C, R, S):
    
    if volume is None :
        result = 0
    elif C is None:
        result = 0
    elif R is None:
        result = 0
    elif S is None:
        result = 0
    else:
        result = N.zeros(len(C), dtype=('float'))
    
    tri_v = N.array(volume, dtype=("float"))
    tri_r = N.array(R, dtype=("float"))
    tri_c = N.array(C, dtype=("float"))
    tri_s = N.array(S, dtype=("float"))
    tri_vol = N.array(volume, dtype=("float"))
    
    xDim = volume.shape[0]
    yDim = volume.shape[1]
    zDim = volume.shape[2]
    
    for i in range(len(C)):
        
        tri_v = TriCubic(tri_c[i], tri_r[i], tri_s[i], volume, xDim, yDim, zDim)
        i = i + 1
    
   # print(tri_v, "tri_v")
    return tri_v
    

def TriCubic ( px,  py,  pz, volume,  xDim,  yDim,  zDim):

    xyDim = xDim * yDim
        
    x = px.astype(int)
    y = py.astype(int)
    z = pz.astype(int)
    
    dx = px -  x
    dy = py -  y
    dz = pz -  z
    
    pv = volume + (x - 1) + (y - 1) * xDim + (z - 1) * xyDim;

    def cube(num):
        return num * num * num
    
    def sqrt(num):
        return num * num 
    
    u = N.array([0,0,0,0], dtype=('float'))
    v = N.array([0,0,0,0], dtype=('float'))
    w = N.array([0,0,0,0], dtype=('float'))
    vox = N.zeros_like(volume, dtype=('float'))
    
    u[0] = -0.5 * cube (dx) + sqrt (dx) - 0.5 * dx;
    u[1] = 1.5 * cube (dx) - 2.5 * sqrt (dx) + 1;
    u[2] = -1.5 * cube (dx) + 2 * sqrt (dx) + 0.5 * dx;
    u[3] = 0.5 * cube (dx) - 0.5 * sqrt (dx);
    
    v[0] = -0.5 * cube (dy) + sqrt (dy) - 0.5 * dy;
    v[1] = 1.5 * cube (dy) - 2.5 * sqrt (dy) + 1;
    v[2] = -1.5 * cube (dy) + 2 * sqrt (dy) + 0.5 * dy;
    v[3] = 0.5 * cube (dy) - 0.5 * sqrt (dy);
    
    w[0] = -0.5 * cube (dz) + sqrt (dz) - 0.5 * dz;
    w[1] = 1.5 * cube (dz) - 2.5 * sqrt (dz) + 1;
    w[2] = -1.5 * cube (dz) + 2 * sqrt (dz) + 0.5 * dz;
    w[3] = 0.5 * cube (dz) - 0.5 * sqrt (dz);
   
    k = 0
    j = 0
    i = 0
    q = [0,0,0,0]
    r = [0,0,0,0]
    
    for k in range(4):
        for j in range(4):
            for i in range(4):
                
                r[j] += u[i] * pv[i]
                i = i+1
                
            q[k] += v[j] * r[j]
            pv += xDim - 4
            j = j+1
            
        vox += w[k] * q[k]
        pv += xyDim - 4 * xDim
        k = k+1
    
    return vox
        
                
    

        
            
            

I am confused on the meaning of some lines. Like these lines...

static PyObject *interp3_tricubic(PyObject *self, PyObject *args);

itr_v = (PyArrayIterObject *) PyArray_IterNew(result);

r[j] += u[i] * *pv;

Please help me correct the code. I am stuck!

Can I convert C program to Python?

Using File I/O we were able to convert C code written in one text file to Python code in another text file with the application of multiple function that could identify and accordingly process specific key words and formats used in the C language.

How do you convert C to F in Python?

Example:.
celsius_1 = float(input("Temperature value in degree Celsius: " )).
# For Converting the temperature to degree Fahrenheit by using the above..
# given formula..
Fahrenheit_1 = (celsius_1 * 1.8) + 32..
# print the result..
print('The %. 2f degree Celsius is equal to: %. ... .
%(celsius_1, Fahrenheit_1)).
print("----OR----").

Is Python created from C?

Python is written in C (actually the default implementation is called CPython).

Can we convert C++ to Python?

If we are speaking fundamentally, then yes you can most definitely convert your C++ program to Python. This is because all programming languages are Turing complete which means that all languages can achieve the same algorithms, solve the same problems, make similar programs, and so on.

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