cdasws

Synopsis

This library provides a simple python interface to the heliophysics data and services of NASA's Coordinated Data Analysis System (CDAS). This library implements the client side of the CDAS RESTful web services and can return data from any of these datasets in a SpacePy datamodel, xarray.Dataset, or pandas.DataFrame with all source and ISTP/SPDF metadata. Frequently asked questions concerning this library are at FAQ. For more general details about the CDAS web services, see https://cdaweb.gsfc.nasa.gov/WebServices/REST/.

Code Example

This package contains example code calling most of the available web services. To run the included example, do the following

python -m cdasws

Also, the following Jupyter notebooks demonstrate different features of the library:

1. Data Retrieval (ipynb file) demonstrating use of library with results returned in SpacePy data model, xarray.Dataset, and pandas.DataFrame. Launch on Binder.
2. CDAWeb Binning Example (ipynb file) demonstrating use CDAWeb binning. Launch on Binder.
3. Magnetic Field Line Conjunction Example (ipynb file) with related data retrieval/plotting using cdasws. Launch on Binder.

And at the bottom of each CDAWeb dataset description is a "Data Access Code Examples" link that contains dataset-specific code utilizing this package to access the data.

Motivation

This library hides the HTTP, JSON/XML, and CDF details of the CDAS web services. A python developer only has to deal with python objects and methods (primarily the SpacePy data model or xarray.Dataset object with full ISTP/SPDF metadata).

Dependencies

The only required dependencies are python-dateutil and requests. If you call the get_data method then one of the following two sets of additional dependencies are required:

1. To have get_data return the data in the SpacePy data model.
   • SpacePy. Refer to the SpacePy documentation for the details of SpacePy's dependencies.
2. To have get_data return the data in an xarray.Dataset or pandas.DataFrame.
   • cdflib.
   • xarray.

Installation

As noted in the dependencies above, if you intend to call the get_data method, you must install one of the following options.

1. SpacePy.

    $ pip install -U spacepy
   

2. cdflib and xarray.

    $ pip install -U cdflib
    $ pip install -U xarray
   

Then, to install this package

$ pip install -U cdasws

API Reference

Refer to cdasws package API reference

or use the standard python help mechanism.

from cdasws import CdasWs
help(CdasWs)

Tests

The tests directory contains unittest tests.

Contributors

Bernie Harris.
e-mail for support.

License

This code is licensed under the NASA Open Source Agreement (NOSA).