Hi everyone!
Im using qiime2-2020.8 on conda.
Im trying to perform ANCOM analysis to compare two samples, from high and low salinity. When I try to do so, I get the following error.
qiime composition ancom
–i-table 3.4-7.7/comp-k-3.4-7.7-18S-table.qza
–m-metadata-file …/Metadata.tsv
–m-metadata-column Salinity
–o-visualization 3.4-7.7/ancom-k.qzv
Plugin error from composition:
All values in
grouping
are unique. This method cannot operate on a grouping vector with only unique values (e.g., there are no ‘within’ variance because each group of samples contains only a single sample).
From this I understand that perhaps you can’t peform this analysis with only two samples.
Is my assumption correct?