specex

This repository contains code for PSF measurement in fiber-fed spectrograph for DESI.

Introduction

This package is intended to be used with the specter extraction code. The installation procedure is described in the INSTALL file, as well as below. The code uses pybind11 (2.2.0)

Installation

git clone --single-branch --branch io_refactor https://github.com/desihub/specex
cd specex
python setup.py install --prefix .

Using specex for DESI

Access to specex in python is through a wrapper specex.specex.run_specex:

from specex.specex import run_specex

com = ['desi_psf_fit']
com.extend(['-a',
            '/global/cfs/cdirs/desi/spectro/redux/blanc/preproc/20201216/00068217/preproc-b1-00068217.fits'])
com.extend(['--in-psf', '/global/cfs/cdirs/desi/spectro/redux/blanc/exposures/20201216/00068217/shifted-input-psf-b1-00068217.fits'])
com.extend(['--out-psf', './fit-psf-b1-00068217-00.fits'])
com.extend(['--first-bundle', '0'])
com.extend(['--last-bundle', '0'])
com.extend(['--first-fiber', '0'])
com.extend(['--last-fiber', '24'])
com.extend(['--legendre-deg-wave', '1'])

retval = run_specex(com)

This should produce a file fit-psf-b1-00068217-00.fits in the same directory.