.. _metadata_fetching:

Fetching Argo meta-data
=======================

Since the Argo measurements dataset is quite complex, it comes with a collection of index files, or lookup tables with meta data. These index help you determine what you can expect before retrieving the full set of measurements. **argopy** has a specific fetcher for index:

.. ipython:: python
    :okwarning:

    from argopy import IndexFetcher as ArgoIndexFetcher

You can use the Index fetcher with the ``region`` or ``float`` access points, similarly to data fetching:

.. ipython:: python
    :suppress:

    import argopy
    ftproot = argopy.tutorial.open_dataset('localftp')[0]
    argopy.set_options(local_ftp=ftproot)

.. ipython:: python
    :okwarning:

    idx = ArgoIndexFetcher(src='localftp').float(2901623).load()
    idx.index

Alternatively, you can use :meth:`argopy.IndexFetcher.to_dataframe()`.

See :ref:`Fetching methods` for a list of all methods available for the Index fetcher.