Astropy has benefited from the addition of widely tested legacy code, as well as new development, resulting in variations in stability across sub-packages. This document summarizes the current status of the Astropy sub-packages, so that users understand where they might expect changes in future, and which sub-packages they can safely use for production code.
The classification is as follows:
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Planned |
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Actively developed, be prepared for possible significant changes. |
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Reasonably stable, any significant changes/additions will generally include backwards-compatiblity. |
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Mature. Additions/improvements possible, but no major changes planned. |
The current planned and existing sub-packages are:
| Sub-Package | Comments | |
|---|---|---|
| astropy.analytic_functions |
|
New in v1.0. |
| astropy.constants |
|
Constants were changed to Quantity objects in v0.2. Since then on, the package has been stable, with occasional additions of new constants. |
| astropy.convolution |
|
New top-level package in v0.3 (was previously part of astropy.nddata). No major changes since, likely will maintain backwards compatibility but possible future additions or improvements. |
| astropy.coordinates |
|
New in v0.2, major changes in v0.4. Subsequent versions should maintain a stable/backwards-compatible API, following the plan of APE 5. Further major additions/enhancements likely, but with basic framework unchanged. |
| astropy.cosmology |
|
Incremental improvements since v0.1, but mostly stable API. Pure functional interface deprecated in v0.4. |
| astropy.io.ascii |
|
Originally developed as asciitable, and has maintained a stable API. |
| astropy.io.fits |
|
Originally developed as pyfits, and retains an API consistent with the standalone version. |
| astropy.io.misc |
|
The functionality that is currently present is stable, but this sub-package will likely see major additions in future. |
| astropy.io.votable |
|
Originally developed as vo.table, and has a stable API. |
| astropy.modeling |
|
New in v0.3. Major changes in v1.0, signficant additions planned. Backwards-compatibility likely to be maintained, but not guaranteed. |
| astropy.nddata |
|
Significantly revised in v1.0 to implement APE 7. Major changes in the API are not anticipated, broader use may reveal flaws that require API changes. |
| astropy.photometry |
|
|
| astropy.stats |
|
Likely to maintain backwards-compatibility, but functionality continually being expanded, so significant additions likely in the future. |
| astropy.table |
|
Incremental improvements since v0.1, but mostly stable API. |
| astropy.time |
|
Incremental improvements since v0.1, API likely to remain stable for the foreseeable future. |
| astropy.units |
|
New in v0.2. Adapted from pnbody and integrated into Astropy. Current functionality stable with intent to maintain backwards compatibility. Significant new functionality is likely to be added in future versions. |
| astropy.utils |
|
Contains mostly utilities destined for internal use with other parts of Astropy. Existing functionality generally stable, but reglar additions and occasional changes. |
| astropy.visualization |
|
New in v1.0, and in development. |
| astropy.vo |
|
Virtual Observatory service access and validation. Currently, only Simple Cone Search and SAMP are supported. |
| astropy.wcs |
|
Originally developed as pywcs, and has a stable API for now. However, there are plans to generalize the WCS interface to accommodate non-FITS WCS transformations, and this may lead to small changes in the user interface. |