import_uparse: Import UPARSE file format


UPARSE is an algorithm for OTU-clustering implemented within usearch. At last check, the UPARSE algortihm was accessed via the -cluster_otu option flag. For details about installing and running usearch, please refer to the usearch website. For details about the output format, please refer to the uparse format definition.


import_uparse(upFile, omitChimeras = TRUE, countTable = TRUE,
  OTUtable = TRUE, verbose = TRUE)



(Required). A file location character string or connection corresponding to the file that contains the UPARSE output table. This is passed directly to fread. Please see its file argument documentation for further links and details.


(Optional). logical(1). Default is TRUE. Whether to omit entries that correspond to sequences/OTUs that were identified as chimeras.


(Optional). logical(1). Default is TRUE. Whether to return the result as a wide-format table with dimensions OTU-by-sample, or to leave the table in its original sparse long-format that might be more suitable for certain data.table operations. If TRUE, entries corresponding to the same sample and OTU have their counts summed.


(Optional). logical(1). Default is TRUE. Whether to coerce the result to otu_table format, or leave it as a data.table format. The former is appropriate for most phyloseq operations, the latter is useful for a lot of custom operations and custom ggplot2 graphics calls.


(Optional). A logical. Default is TRUE. Should progresss messages be catted to standard out?


Because UPARSE is an external (non-R) application, there is no direct way to continuously check that these suggested arguments and file formats will remain in their current state. If there is a problem, please verify your version of usearch, create a small reproducible example of the problem, and post it as an issue on the phyloseq issues tracker.

See Also




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