Some tools written in Interactive Data Language (IDL)

The Interactive Data Language

IDL is a programming language for scientific data analyses. It is widely used in the astronomical community, and has a rich astronomical library maintained by NASA (The IDL Astronomy User's Library). This page provides some useful IDL tools written by me.

A quick start guide to IDL

SIMPLE Imaging and Mosaicking PipeLinE (SIMPLE)

SIMPLE is an IDL based data reduction package for optical and near-infrared imaging, particularly for mosaic cameras. Currently it is optimized for MOIRCS (Subaru) and WIRCam (CFHT). A version for WFCAM (UKIRT) is being developed. A less tailored version for MegaCam (CFHT) also exists.

Learn More

 

Some Useful Tools

Routine Description
create_gauss_beam.pro Generate a 2-D circular Gaussian.
create_uniform_beam.pro Generate a circular aperture with identical values.
create_seeing_psf.pro Generate a circular exp[-r^(5/3)] seeing PSF.
cross_cats.pro Cross-match two catalogs and find overlapping objects. Useful for dealing with multi-wavelength catalogs. A subroutine cross_dogs.pro is required.
hexpand.pro Expand an image and update header astrometry.
mask_polygon.pro Mask polygon regions in an image.
merge_vector.pro Merge two vectors into one.
sexfind.pro Detect objects in an image. This was written to replace find.pro in the IDL Astronomy Library, by using the SExtractor package, which is quite standard in extragalactic astronomy for generating source catalogs. Comparing to find.pro, sexfind.pro produces better flux measurements and more accurate source positions. To use this, you must have both the IDL Astronomy Library (how to?) and SExtractor installed in your system, and the subroutine my_read_ascii.pro in your working directory or included in the IDL library. You also need to have a SExtractor configuration file and a catalog parameter file in your working directory. Here are examples of the configuration file sexfind.default and parameter file sexfind.param.
write_ds9reg.pro Write a set of RA/Dec or x/y circles into ds9's reg file. Useful to see how a catalog and an image match.