A SkyCalc wrapper for Interactive Python

Welcome to the SkyCalc-iPy Documentation!

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A SkyCalc wrapper for Interactive Python#

SkyCalc-iPy (“SkyCalc for Interactive PYthon”) is a package for accessing atmospheric emission and transmission data generated by ESO’s SkyCalc tool interactively with Python.

This package is based on the command line tool by ESO for accessing spectra on the ESO SkyCalc server. For references to SkyCalc see ESO SkyCalc, Noll et al. (2012), and Jones et al. (2013).

Changed in version v0.4.0: Drop support for Python 3.8.

Changed in version v0.2.0: Hotfix for new ESO ETC server.

The new ESO ETC server uses different units, which are now used.

Changed in version v0.1.5: Hotfix to replace ESO ETC server URL.

Skycalc now uses https://etimecalret-002.eso.org as server, #25.

Changed in version v0.1.4: Drop support for Python 3.7.

Skycalc now uses pyproject.toml, and only supports Python 3.8+.

Changed in version v0.1.3: Updated default values for wmax, wgrid_mode, wres

SkyCalc-ipy now uses a logarithmic wavelength binning with R=1000 over the fully available SkyCalc wavelength range of [0.3, 30] um

  • wmax: –> 30000 # [nm]

  • wgrid_mode: –> fixed_spectral_resolution

  • wres: –> 1000 wave/dwave

Changed in version v0.1.3: No longer saves a temporary FITS file to disk.

SkyCalc now uses astropy to download the fits file from the SkyCalc server. The HDUList is now stored internally in <SkyCalc>.last_skycalc_response.

Changed in version v0.1.2: Upgrade fixes PyYaml warning/error for PyYaml >=6.0

SkyCalc-ipy v0.1.1 is only compatible with versions of PyYaml <=5.4. PyYaml v6+ removed backwards compatibility by forcing the user to pass a Loader object when reading YAML files. SkyCalc-ipy v0.1.0 and v0.1.1 does not do this.


Skycalc_ipy is available on PyPi:

pip install skycalc_ipy

This is still the very first version of SkyCalc iPy, so please open an issue on GithHub if you find any bugs, or if would like to see different functionality included.



The following packages are required for normal operation:

  • httpx

  • pyyaml

  • numpy

  • astropy

  • astar-utils

The following packages are optional:

  • matplotlib

  • synphot