ogip 0.2.1

ogip

# Python library to read, write, and validate “OGIP” files

[](https://travis-ci.com/volodymyrss/ogip)[](https://codecov.io/gh/volodymyrss/ogip)

• aims to support OGIP formats: * [OGIP/92-007 (The OGIP Spectral File Format)](https://heasarc.gsfc.nasa.gov/docs/heasarc/ofwg/docs/spectra/ogip_92_007/node5.html) * [OGIP Calibration Memo CAL/GEN/92-002 (The Calibration Requirements for Spectral Analysis, Definition of RMF and ARF file formats)](https://heasarc.gsfc.nasa.gov/docs/heasarc/caldb/docs/memos/cal_gen_92_002/cal_gen_92_002.html) * [OGIP Memo OGIP/93-003 (The Proposed Timing FITS File Format for High Energy Astrophysics Data)](https://heasarc.gsfc.nasa.gov/docs/heasarc/ofwg/docs/rates/ogip_93_003/ogip_93_003.html).

• does not aim to implement the strictest form of the standard, instead trying to understand the content from the least information provided, following [Postel’s](https://en.wikipedia.org/wiki/Robustness_principle) [Law](https://tools.ietf.org/html/rfc1122) (which has proven to be successful in TCP).

• well-defined, versioned, and provenance-committed process

• it just works, always while it is also always possible to recover what exactly was done and why.

• relies only on [astropy](https://www.astropy.org/)

Existing alternatives:

• [heasoft](https://heasarc.gsfc.nasa.gov/lheasoft/) contains pyxpec and heasp modules, which read ogip files.

• [sherpa](https://cxc.cfa.harvard.edu/sherpa/) and [3ml](https://github.com/threeML/threeML/) can read and write ogip files

The alertnatives share common disadvantage: they are complex and not easily portable packages. Also, they implement different variations of the standards, and we have a different aim here (see above).

## Disadvantages:

• only python, hence slow

## Example

`python # opens a file, detects format, writes ogip.core.open_something("file.fits").to_fits('output_file.fits') `