source: trunk/src/FitsIO/dataIO.cc @ 220

#include <iostream>
#include <string>
#define WCSLIB_GETWCSTAB // define this so that we don't try and redefine 
                         //  wtbarr (this is a problem when using gcc v.4+
#include <fitsio.h>
#include <math.h>
#include <duchamp.hh>
#include <Cubes/cubes.hh>

int Cube::getFITSdata(string fname)
{
  /**
   * This function retrieves the data array from the FITS file at the 
   *   location given by the string argument.
   *  Only the two spatial axes and the one spectral axis are stored in the
   *   data array. These axes are given by the wcsprm variables wcs->lng, 
   *   wcs->lat and wcs->spec. 
   *  All other axes are just read by their first pixel, using the 
   *   fits_read_subsetnull_ functions
   */

  long nelements;
  int bitpix,numAxes;
  int status = 0,  nkeys;  /* MUST initialize status */
  fitsfile *fptr;  

  // Open the FITS file
  status = 0;
  if( fits_open_file(&fptr,fname.c_str(),READONLY,&status) ){
    fits_report_error(stderr, status);
    return FAILURE;
  }

  // Read the size of the FITS file -- number and sizes of the axes
  status = 0;
  if(fits_get_img_dim(fptr, &numAxes, &status)){
    fits_report_error(stderr, status);
    return FAILURE;
  }
  long *dimAxes = new long[numAxes];
  for(int i=0;i<numAxes;i++) dimAxes[i]=1;
  status = 0;
  if(fits_get_img_size(fptr, numAxes, dimAxes, &status)){
    fits_report_error(stderr, status);
    return FAILURE;
  }

  // Identify which axes are the "interesting" ones 
  int lng,lat,spc;
  if(this->head.isWCS()){
    lng = this->head.getWCS()->lng;
    lat = this->head.getWCS()->lat;
    spc = this->head.getWCS()->spec;
  }
  else{
    lng = 0;
    lat = 1;
    spc = 2;
  }
    

  int anynul;
  int npix = dimAxes[lng]*dimAxes[lat]*dimAxes[spc];

  float *pixarray = new float[npix];// the array of pixel values
  char *nullarray = new char[npix]; // the array of null pixels
  long *inc = new long[numAxes];    // the data-sampling increment

  // define the first and last pixels for each axis.
  // set both to 1 for the axes we don't want, and to the full
  //  range for the ones we do.
  long *fpixel = new long[numAxes];
  long *lpixel = new long[numAxes];
  for(int i=0;i<numAxes;i++){
    inc[i] = fpixel[i] = lpixel[i] = 1;
  }
  lpixel[lng] = dimAxes[lng];
  lpixel[lat] = dimAxes[lat];
  lpixel[spc] = dimAxes[spc];
    
  int colnum = 0;  // want the first dataset in the FITS file

  // prepare the Cube's pixel array -- so that we don't have to use saveArray;
//   if(this->numPixels>0) delete [] array;
//   this->array = new float[npix];
//   this->numPixels = npix;
  // read the relevant subset, defined by the first & last pixel ranges
  status = 0;
  if(fits_read_subsetnull_flt(fptr, colnum, numAxes, dimAxes,
                              fpixel, lpixel, inc, 
//                            this->array, nullarray, &anynul, &status)){
                              pixarray, nullarray, &anynul, &status)){
    duchampError("getFITSdata",
                 "There was an error reading in the data array:");
    fits_report_error(stderr, status);
    return FAILURE;
  }

  delete [] fpixel;
  delete [] lpixel;
  delete [] inc;

  if(anynul==0){    
    // no blank pixels, so don't bother with any trimming or checking...
    if(this->par.getFlagBlankPix()) {  
      // if user requested fixing, inform them of change.
      duchampWarning("getFITSdata",
                     "No blank pixels, so setting flagBlankPix to false.\n");
    }
    this->par.setFlagBlankPix(false); 
  }

  this->initialiseCube(dimAxes);
  this->saveArray(pixarray,npix);
  delete [] pixarray;
  delete [] dimAxes;
  this->par.setOffsets(this->head.getWCS());
  //-------------------------------------------------------------
  // Once the array is saved, change the value of the blank pixels from
  // 0 (as they are set by fits_read_pixnull) to the correct blank value
  // as determined by the above code.
  for(int i=0; i<npix;i++){
//     if(nullarray[i]==1) this->array[i] = blank*bscale + bzero;  
//     if(isnan(array[i])) this->array[i] = par.getBlankPixVal();
    if(nullarray[i]==1) this->array[i] = this->par.getBlankPixVal();  
  }

  delete [] nullarray;
  // Close the FITS file -- not needed any more in this function.
  status = 0;
  fits_close_file(fptr, &status);
  if (status){
    duchampWarning("defineWCS","Error closing file: ");
    fits_report_error(stderr, status);
  }

  return SUCCESS;

}