Installing HUMAnN3 with conda

I am trying to install HUMAnN3 using the following commands
conda create --name biobakery3 python=3.7
source activate biobakery3
conda install humann -c biobakery

but I am stuck on this message

  • humann -> metaphlan >=3.0.0.alpha

When I tried to install metaphlan separately by using
conda install metaphlan -c bioconda

I get
UnsatisfiableError: The following specifications were found to be in conflict:

  • metaphlan -> biom-format -> pyqi ==0.3.1 -> python 2.7* -> openssl 1.0.1*
  • metaphlan -> biom-format -> pyqi ==0.3.1 -> python 2.7* -> readline 6.2*
  • metaphlan -> biom-format -> pyqi ==0.3.1 -> python 2.7* -> tk 8.5*
  • python 3.7*

I tried to use python 2.7 and get this error instead.

  • metaphlan -> matplotlib-base -> python >=3.6,<3.7.0a0
  • python 2.7*

Seems like I need python 2.7 for pyqi, but python 3.6 for metaphlan. Is there something I need to do in my setting to be able to set up a HUMAnN3 conda envirment?

Hmm, I haven’t seen this. Sometimes conda installation problems are related to the priority of the channels it’s drawing from. MetaPhlAn comes from bioconda and they recommend a specific channel priority for installation:

I also had problems running the the latest humann. It failed at installing the latest metaphlan’s mpa tar file. Installing humann via conda did not install the latest metaphlan build.

What worked for me is to specify the build when installing: conda install metaphlan=3.0=pyh5ca1d4c_2 --no-channel-priority

The parameter --no-channel-priority may not be necessary

Without specifying the build when installing it will install the older build pyh5ca1d4c_1 instead

Thank you both for answering my question.

Setting up the bioconda channel priority fixed the problem for me!

Great! I’ll add a note about that to the install instructions.

Just an follow up on this.
Although the test ran fine, when I tried to run my own samples, it gave me an error message. I used aimirza’s suggestion and updated metaphlan. It works fine after that.