Metadata-Version: 2.1
Name: deproject
Version: 0.2.0
Summary: Sherpa deprojection package (X-ray analysis of Galaxy Clusters, Groups, and Galaxies)
Home-page: https://deproject.readthedocs.io/
Author: Douglas Burke, Tom Aldcroft
Author-email: dburke.gw@gmail.com
License: BSD
Project-URL: Documentation, https://deproject.readthedocs.io/
Project-URL: Issues, https://github.com/sherpa-deproject/deproject/issues/
Project-URL: Source Code, https://github.com/sherpa-deproject/deproject/
Description: Deproject
        =========
        
        ``Deproject`` is a `Sherpa <https://sherpa.readthedocs.io/>`_ extension package
        to facilitate deprojection of two-dimensional annular X-ray spectra to recover
        the three-dimensional source properties.  For typical thermal models this would
        include the radial temperature and density profiles. This basic method has been
        used extensively for X-ray cluster analysis and is the basis for the XSPEC
        model ``projct``.  The ``deproject`` module brings this functionality to
        *Sherpa* as a Python module that is straightforward to use and understand.
        
        The basic physical assumption of ``deproject`` is that the extended source
        emissivity is constant and optically thin within spherical shells whose radii
        correspond to the annuli used to extract the specta.  Given this assumption one
        constructs a model for each annular spectrum that is a linear volume-weighted
        combination of shell models.
        
        Version 0.2 of ``deproject`` is limited to circular annuli.
        
        Further documentation is available at https://deproject.readthedocs.io/
        
        License
        -------
        
        The ``deproject`` module is released under the
        `BSD 2-Clause license <https://choosealicense.com/licenses/bsd-2-clause/>`_,
        available as the file ``LICENSE`` in the source distribution.
        
        Requirements
        ------------
        
        The installation assumes that you are installing ``deproject`` into
        the `CIAO environment <http://cxc.harvard.edu/ciao/>`_ (CIAO 4.11 or
        later), since this is the easiest way to get the XSPEC models along
        with Sherpa. The `standalone Sherpa <https://sherpa.readthedocs.io/>`_
        version can be used, but in this case you will need to `build Sherpa
        with XSPEC support
        <https://sherpa.readthedocs.io/en/latest/install.html#xspec>`_.
        
        The following Python packages are required:
        
         - sherpa
         - `Astropy <http://www.astropy.org/>`_ (restricted to version 3.0 when
           using CIAO 4.11)
         - `SciPy <https://www.scipy.org/scipylib/>`_.
        
        Installation
        ------------
        
        The ``deproject`` module should install with the following command
        (assuming CIAO 4.11 is already installed):
        
          echo "numpy==1.12.1" > constraints.txt
          pip install -c constraints.txt 'astropy<3.1' deproject
        
        Example
        -------
        
        If you have a set of X-ray PHA spectra called src<n>.pi, where <n> is
        an integer representing the annulus number, and the files contain the
        ``XFLT0001`` to ``XFLT0005`` header keywords used by the
        `XSPEC projct model <https://asd.gsfc.nasa.gov/XSPECwiki/projct_model>`_,
        then a
        `Deproject object <https://deproject-test.readthedocs.io/en/latest/modules/api/deproject.deproject.Deproject.html#deproject.deproject.Deproject>`_
        can be created using the
        `deproject_from_xflt <https://deproject-test.readthedocs.io/en/ciao-411/modules/api/deproject.deproject.deproject_from_xflt.html>`_
        helper routine with the commands:
        
          >>> from deproject import deproject_from_xflt
          >>> from astropy import units as u
          >>> dep = deproject_from_xflt('src*.pi', 0.492 * u.arcsec)
        
        where, in this example, the ``XFLT0001`` and ``XFLT0002`` keywords,
        which specify the inner and outer radii of the annulus, are in
        ACIS pixels, and so need to be multiplied by 0.492 arcseconds to
        convert to an angle (the second parameter).
        
        This will automatically load the spectra into separate Sherpa datasets,
        which *can* be fitted individually, but it is generally easier to use
        the object returned by ``deproject_from_xflt``. For instance, the
        following will set the data range to be fit for *each* spectra and ensure
        that the background is subtracted before fitting:
        
          >>> dep.ignore(None, 0.5)
          >>> dep.ignore(7.0, None)
          >>> dep.subtract()
        
        Sherpa functions are used to change the statistic and optimiser:
        
          >>> from sherpa.astro import ui
          >>> ui.set_stat('chi2xspecvar')
          >>> ui.set_method('levmar')
        
        The data can be fit, and errors estimated for all the parameter, using
        the onion-skin deprojection approach, with the following commands:
        
          >>> onion = dep.fit()
          >>> errs = dep.conf()
        
        The return value includes the density (and errors, if appropriate), as
        an `Astropy Quantity <http://docs.astropy.org/en/stable/units/>`_.
        
          >>> print(onion['density'])
          print(onion['density'])
                density
                1 / cm3
          --------------------
            0.1100953546292787
           0.07736622021374819
           0.04164827967805805
           0.03630168106524076
          0.025221797991301052
          0.021845331641349316
                           ...
          0.012396857131392835
           0.01336640115325031
          0.012303975980575187
          0.013631563529090736
          0.013996131292837352
          0.010843683594144967
          0.023067220584935984
          Length = 20 rows
        
        The `on-line documentation <https://deproject.readthedocs.io/>`_
        contains more information, including creating the ``Deproject`` object
        directly (without the need for the ``XFLTxxxx`` keywords).
        
Keywords: deprojection xray 3d 2d plasma Astrophysics onion
Platform: UNKNOWN
Classifier: Development Status :: 4 - Beta
Classifier: Intended Audience :: Science/Research
Classifier: License :: OSI Approved :: BSD License
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: 3.6
Classifier: Programming Language :: Python :: 3.7
Classifier: Topic :: Scientific/Engineering :: Astronomy
Classifier: Topic :: Scientific/Engineering :: Physics
Requires-Python: ~=3.5
Description-Content-Type: text/x-rst
