.. _pydl.pydlutils: ================================= SDSS Utilities (`pydl.pydlutils`) ================================= Introduction ++++++++++++ This package provides functionality similar to idlutils_, a general suite of tools heavily used by SDSS_. idlutils_ is itself divided into a number of subpackages. Below we list the subpackages and the usability of the PyDL equivalent. The readiness levels are defined as: Obsolete No point in implementing because the purpose of the code lapsed many years ago. Not Applicable (NA) No point in implementing because another built-in or numpy/scipy/astropy package completely replaces this. None Not (yet) implemented at all. Rudimentary Only a few functions are implemented. Fair Enough functions are implemented to be useful, but some are missing. Good Pretty much anything you could do with the idlutils code you can do with the equivalent here. =========== =============== =================================================== Subpackage Readiness Level Comments =========== =============== =================================================== 2mass None For use with matching 2MASS catalogs to SDSS data. astrom None For use with SDSS astrometric data structures. Largely superseded by WCS. bspline Good Fitting B-splines to data, especially for resampling. cooling Good See :func:`pydl.pydlutils.cooling.read_ds_cooling`. coord Fair Some functionality already provided by :mod:`astropy.coordinates`. cosmography NA Tools for computing lookback time, angular sizes at cosmological distances, etc. Use :mod:`astropy.cosmology`. dimage None Interface to C code used for sky subtraction. djsphot None A simple aperture photometry code. dust None For use with the SFD galactic dust map. first None For use with matching FIRST catalogs to SDSS data. fits NA Use :mod:`astropy.io.fits`. healpix NA Interact with HEALPix data. Use healpy_. image Rudimentary Image manipulation functions. json NA Use :mod:`json` or other packages. mangle Fair Some work still required on polygon area calculations. math Fair Generic mathematical functions. Many are implemented in numpy or scipy. mcmc None But there are plenty of good Python MCMC packages out there. mglib Obsolete An IDL object-oriented configuration file reader. misc Fair General purpose utility functions. mpeg None Wrapper for :command:`ppmtompeg`, makes movies from data. mpfit None Appears to be an out-of-sync copy of the "markwardt" package in the `The IDL® Astronomy User's Libary`_. physics None Implementation of physical formulas, *e.g.* free-free scattering. plot None Much functionality already exists in matplotlib. psf Obsolete Point-spread function fitting. rgbcolor Good Some functionality is duplicated in :mod:`astropy.visualization`, especially :func:`~astropy.visualization.make_lupton_rgb`. rosat None For use with matching ROSAT catalogs to SDSS data. sdss Good Most important functionalities are bitmasks_ and reading `sweep files`_. slatec None Fit B-splines using C code. spheregroup Good Used for matching arbitrary RA, Dec coordinates to other arbitrary RA, Dec coordinates. TeXtoIDL NA This package is for including TeX in IDL plots. Since matplotlib understands TeX natively, this is not needed. trace Fair Used for fitting orthogonal functions to spectroscopic wavelength solutions. ukidss None Used for matching UKIDSS catalogs to SDSS data. wise None Used for matching WISE catalogs to SDSS data. yanny Good Tools for manipulating `SDSS parameter files`_. =========== =============== =================================================== .. _idlutils: https://www.sdss.org/dr16/software/idlutils/ .. _SDSS: https://www.sdss.org .. _`The IDL® Astronomy User's Libary`: https://idlastro.gsfc.nasa.gov/ .. _healpy: https://healpy.readthedocs.io/en/latest/ .. _bitmasks: https://www.sdss.org/dr16/algorithms/bitmasks/ .. _`sweep files`: https://data.sdss.org/datamodel/files/PHOTO_SWEEP/RERUN/calibObj.html .. _`SDSS parameter files`: https://www.sdss.org/dr16/software/par/ API +++ .. automodapi:: pydl.pydlutils .. automodapi:: pydl.pydlutils.bspline :skip: warn, PydlutilsUserWarning, djs_reject, fchebyshev, uniq, flegendre, cholesky_banded, LinAlgError, cho_solve_banded .. automodapi:: pydl.pydlutils.cooling :skip: interp, get_pkg_data_contents .. automodapi:: pydl.pydlutils.coord :skip: get_juldate .. automodapi:: pydl.pydlutils.image .. automodapi:: pydl.pydlutils.mangle :skip: PydlutilsException, PydlutilsUserWarning .. automodapi:: pydl.pydlutils.math :skip: svd, djs_laxisnum, median .. automodapi:: pydl.pydlutils.misc .. automodapi:: pydl.pydlutils.rgbcolor :skip: warn .. automodapi:: pydl.pydlutils.sdss :skip: download_file, spherematch, uniq .. automodapi:: pydl.pydlutils.spheregroup :skip: warn, PydlutilsException, PydlutilsUserWarning, gcirc .. automodapi:: pydl.pydlutils.trace :skip: chebyt, FITS_rec, PydlutilsException, djs_reject, djs_laxisgen, flegendre .. automodapi:: pydl.pydlutils.yanny :skip: OrderedDict, PydlutilsException, PydlutilsUserWarning, Table