I tried to examine the Blast classifier for the first time to have its output then compare it to others, but it does not run because of the the comment that I did not understand. I need you to give me a hint why did not it run?

qiime feature-classifier classify-consensus-blast \

–i-query mergedseq.qza
–i-reference-reads RefRead.qza
–i-reference-taxonomy RefTaxonomy.qza
–p-strand ‘plus’
–p-unassignable-label unassigned
–o-classification SILVA-Blast-barplot.qza

Running external command line application. This may print messages to stdout and/or stderr.
The command being run is below. This command cannot be manually re-run as it will depend on temporary files that no longer exist.

Command: blastn -query /tmp/qiime2-archive-_23tpuac/e8de5a5c-545a-4917-8e2d-7a8edab2ef6d/data/dna-sequences.fasta -evalue 0.001 -strand plus -outfmt 7 -subject /tmp/qiime2-archive-28b86uag/7fb65b6d-f8ac-4233-a5a9-29d2ca9619dd/data/dna-sequences.fasta -perc_identity 80.0 -qcov_hsp_perc 80.0 -max_target_seqs 10 -out /tmp/tmpou2l_fbc

Also, as you see, I did not use these parameters:

–p-maxaccepts INTEGER Maximum number of hits to keep for each query. Must
Range(1, None) be in range [1, infinity]. BLAST will choose the
first N hits in the reference database that exceed
perc-identity similarity to query. [default: 10]
–p-perc-identity PROPORTION Range(0.0, 1.0, inclusive_end=True)
Reject match if percent identity to query is lower.
Must be in range [0.0, 1.0]. [default: 0.8]
–p-query-cov PROPORTION Range(0.0, 1.0, inclusive_end=True)
Reject match if query alignment coverage per
high-scoring pair is lower. Note: this uses blastn’s
qcov_hsp_perc parameter, and may not behave
identically to the query-cov parameter used by
classify-consensus-vsearch. Must be in range [0.0,

I would like to know based on what criteria can I determine an appropriate integers for each parameter? Is it OK with default? Or I have to change them according to my project circumstances?

This means that command is running, so just give it time

I don’t see an error message

Defaults are fine. We optimized these parameters for use with 16S and ITS data, see here for the citation of this method, more description, description of the defaults, and guidelines for adjusting these parameters.

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‘It says cannot be manually re-run__ need files that I do not know what files it needs’
thank you

Not an error, just a warning.

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