Merge pull request #55 from AstarVienna/fh/readme

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README.md

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+# ScopeSim Templates
+
+[![Build Status](https://github.com/AstarVienna/ScopeSim_Templates/actions/workflows/tests.yml/badge.svg)](https://github.com/AstarVienna/ScopeSim_Templates/actions/workflows/tests.yml/badge.svg)
+[![Documentation Status](https://readthedocs.org/projects/scopesim-templates/badge/?version=latest)](https://scopesim-templates.readthedocs.io/en/latest)
+[![Codecov](https://img.shields.io/codecov/c/github/AstarVienna/ScopeSim_Templates/\branch/dev_master?logo=codecov)](https://app.codecov.io/gh/AstarVienna/ScopeSim_Templates/tree/dev_master)
+[![PyPI - Version](https://img.shields.io/pypi/v/ScopeSim-Templates)](https://pypi.org/project/ScopeSim-Templates/)
+
+[![License: GPL v3](https://img.shields.io/badge/License-GPLv3-blue.svg)](https://www.gnu.org/licenses/gpl-3.0)
+
+This packages contain a number of templates to generate `Source` objects to be used in simulations with the [ScopeSim Simulator](https://scopesim.readthedocs.io/en/latest/)
+
+The Documentation can be found here: https://scopesim-templates.readthedocs.io/en/latest
+
+## Installation
+
+The best way to install the software is to use `pip`
+
+``` bash
+pip install scopesim_templates
+```
+
+To install the development version you can clone the repository
+
+``` bash
+git clone https://github.com/AstarVienna/ScopeSim_Templates/
+cd ScopeSim_Templates
+pip install -e .
+```
+
+## Requirements
+
+- numpy
+- astropy
+- [synphot](https://synphot.readthedocs.io/en/latest/index.html)
+- [ScopeSim](https://scopesim.readthedocs.io/en/latest/)
+- [speXtra](https://spextra.readthedocs.io/en/latest/)
+- [pyckles](https://pyckles.readthedocs.io/en/latest/)
+
+## The `Source` object
+
+The above functions are created to easy the creation of standard sources but the power of the `Source` object doesn't end there and can be used to create endless sources possibilities.
+
+In a nutshell a `Source` object contains a spacial and spectral description of the sources. The spectral description are in the form of `synphot` spectra and the spacial description can be an `astropy` table referencing the spectra or a fits image. `Source` can also accept datacubes. The `speXtra` package contains an extensive library of spectral templates that can be used with the sources. Please check the relevant documentation.
+
+## `Source` templates included
+
+Currently, the package covers the most typical sources used in astronomy:
+
+- `stellar`
+  - `star`: Places a single star on the field
+  - `stars`: Places a list of stars on the field
+  - `star_field`: Creates field of stars with random positions
+  - `star_grid`: Creates a field of stars with regular positions
+  - `cluster`: Creates an age=0 cluster with a user selected mass
+
+- `extragalactic`  
+  - `galaxy`: A simple sersic model with a user selected SED from the `speXtra` database
+  - `galaxy3D`: A more complex model that includes a velocity field and velocity dispersion field
+  - `spiral_two_component`: Simple two component model with an outer spiral young SED and an old SED bulge
+  - `elliptical`: Another sersic model using the Brown SEDs
+
+- `misc`  
+  - `point_source`: similar to `star` but using any SED from the `speXtra` database
+  - `uniform_source`: Creates a uniform source with any SED from `speXtra`
+  - `source_from_file`: Load the source from a fits file. Depending on the characteristics othe functions may be more suitable
+  - `source_from_imagehdu`: creates a source from an `ImageHDU` with an arbitrary flux and scale
+  - `source_from_imagehdu_with_flux`: creates a source from an `ImageHDU` where the flux/pixel is known
+  - `source_from_array`: General function to create a source from a 2D `numpy` array
+  - `source_from_cube`: Wrapper to create a source from a 3D datacube
+
+- `calibration`  
+  - `lamp`: Simulates a calibration lamp, i.e. a homogenous source with emissions lines
+  - `flat_field`: Simulates a flat field
+  - `empty_sky`: To simulate a sky without no other sources
+
+Please see the documentation how to use each particular source and contact us (raise an issue or submit a pull request) if more specialized sources are needed.