Questions about demultiplexing sequences

[kaile]

Hi,
I have got a problem when I try to demultiplex sequences. Below are my commands.

qiime tools import
--type 'SampleData[SequencesWithQuality]'
--input-path trimmed-seq
--input-format CasavaOneEightSingleLanePerSampleDirFmt
--output-path demux-single-end.qza

qiime demux emp-single
--i-seqs demux-single-end.qza
--m-barcodes-file sample-metadata.txt
--m-barcodes-column BarcodeSequence
--o-per-sample-sequences demux.qza
--o-error-correction-details demux-details.qza

Error:
(1/1) Invalid value for "--i-seqs": Expected an artifact of at least type
RawSequences | EMPSingleEndSequences | EMPPairedEndSequences. An artifact of type SampleData[SequencesWithQuality] was provided.

How to fix it?

[ChrisKeefe]

Hi @kaile! Have you looked over the importing tutorial?

Because you're using Casava, I suspect your sequences are already demultiplexed. The error message is telling you that qiime demux expects RawSequences (or similar), and you're handing it SampleData, which has already been split into samples.

Best,
Chris