def MRA(biomf, sampleIDs=None, transform=None):
ra = relative_abundance(biomf, sampleIDs)<EOL>if transform is not None:<EOL><INDENT>ra = {sample: {otuID: transform(abd) for otuID, abd in ra[sample].items()}<EOL>for sample in ra.keys()}<EOL><DEDENT>otuIDs = biomf.ids(axis="<STR_LIT>")<EOL>return mean_otu_pct_abundance(ra, otuIDs)<EOL>
Calculate the mean relative abundance percentage.

:type biomf: A BIOM file.
:param biomf: OTU table format.

:type sampleIDs: list
:param sampleIDs: A list of sample id's from BIOM format OTU table.

:param transform: Mathematical function which is used to transform smax to another
                  format. By default, the function has been set to None.

:rtype: dict
:return: A dictionary keyed on OTUID's and their mean relative abundance for a given
         number of sampleIDs.