# Demux summarize on already demultiplexed data

**URL:** <https://forum.qiime2.org/t/demux-summarize-on-already-demultiplexed-data/1100>\
**Category:** User Support\
**Tags:** matplotlib\
**Created:** [August 28, 2017, 4:37pm UTC](https://forum.qiime2.org/t/demux-summarize-on-already-demultiplexed-data/1100 "2017-08-28T16:37:31Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![morganpuff](https://forum.qiime2.org/user_avatar/forum.qiime2.org/morganpuff/32/5446_2.png) [@morganpuff](https://forum.qiime2.org/u/morganpuff)\
**Post date:** [August 28, 2017, 4:37pm UTC](https://forum.qiime2.org/t/demux-summarize-on-already-demultiplexed-data/1100/1 "2017-08-28T16:37:31Z")

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I have paired-end data that is already demultiplexed and imported using the generic fastq commands. However, to move on to any quality filtering I have to be able to view the summary of the demultiplexing results, am I correct?

This is the command I run:

```
qiime demux summarize \
  --i-data paired-end-demux.qza \
  --o-visualization demux.qzv

```

When I run the summary table command, I receive the error:

```
Plugin error from demux:

  Invalid DISPLAY variable

Debug info has been saved to /tmp/qiime2-q2cli-err-zoh9ypke.log.

```

Is there a suggested method for data that is paired-end and already demultiplexed to move on to the quality filtering step?

Let me know if I need to provide more information.

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**Author:** ![jairideout](https://forum.qiime2.org/user_avatar/forum.qiime2.org/jairideout/32/9_2.png) [@jairideout](https://forum.qiime2.org/u/jairideout)\
**Post date:** [August 31, 2017, 1:25am UTC](https://forum.qiime2.org/t/demux-summarize-on-already-demultiplexed-data/1100/3 "2017-08-31T01:25:40Z")

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Hi @morganpuff! This error isn't related to your data or `qiime demux summarize`, it's a system configuration issue with your matplotlib installation. matplotlib's default configuration requires a display, which you don't appear to have (this is common if you're logged into a server and don't have an X server and X-forwarding set up).

This topic will show you how to configure matplotlib to work in a headless environment. Get in touch if you have any issues!

> [@Error in qiime feature-table summarize](https://forum.qiime2.org/t/error-in-qiime-feature-table-summarize/308):
>
> Good morning, When trying to summarize a merged table from 4 denoised sequence variant data I got the following error: What is this DISPLAY variable? And how can I fix it? Thank you! (qiime2) ekg43@thompson:~/SCC/Dada$ qiime feature-table summarize --i-table table1234.qza --o-visualization table1234 Traceback (most recent call last): File "/home/ekg43/miniconda3/envs/qiime2/bin/qiime", line 6, in \<module\> sys.exit(q2cli.\_\_main\_\_.qiime()) File "/home/ekg43/miniconda3/envs/qiime2/lib/p…

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**Author:** ![system](https://forum-qiime2-org.s3.dualstack.us-west-2.amazonaws.com/original/3X/2/1/21af5fe23cb6f4579467c66a9ed94e55274ca7bd.svg) [@system](https://forum.qiime2.org/u/system)\
**Post date:** [October 1, 2017, 7:25am UTC](https://forum.qiime2.org/t/demux-summarize-on-already-demultiplexed-data/1100/5 "2017-10-01T07:25:58Z")

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