Logo ROOT   6.14/05
Reference Guide
FITS_tutorial7.C File Reference

Detailed Description

Open a FITS file that contains a catalog of astronomical objects and dump some of its columns.

void FITS_tutorial7()
{
printf("\n\n--------------------------------\n");
printf("WELCOME TO FITS tutorial #7 !!!!\n");
printf("--------------------------------\n");
printf("We are going to open a table from a FITS file\n");
printf("and print out three columns for some of the objects.\n");
printf("This table contains a logical data type so this tutorial tests\n");
printf("that we can read it correctly\n\n");
TString dir = gSystem->DirName(__FILE__);
// Open the table
TFITSHDU *hdu = new TFITSHDU(dir + "/sample5.fits[1]");
if (hdu == 0) {
printf("ERROR: could not access the HDU\n");
return;
}
TVectorD *vec1;
TVectorD *vec2;
TVectorD *vec3;
TVectorD *vec4;
// Read the ra, dec, flux_g and brick_primary columns
vec1 = hdu->GetTabRealVectorColumn("ra");
vec2 = hdu->GetTabRealVectorColumn("dec");
vec3 = hdu->GetTabRealVectorColumn("flux_g");
vec4 = hdu->GetTabRealVectorColumn("brick_primary");
Double_t gflux, ra, dec, bp;
for (Int_t i = vec1->GetLwb(); i <= vec1->GetUpb(); i++) {
bp = (*vec4)[i];
gflux = (*vec3)[i];
ra = (*vec1)[i];
dec = (*vec2)[i];
if (bp) {
printf("RA %f DEC %f G-FLUX %f\n", ra, dec, gflux);
}
}
// Clean up
delete vec1;
delete vec2;
delete vec3;
delete vec4;
delete hdu;
}
Author
Elizabeth Buckley-Geer

Definition in file FITS_tutorial7.C.