# Python conda installation Formula Errors **URL:** \ **Category:** Installation\ **Tags:** Python\ **Created:** [18 August 2020 00:24 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412 "2020-08-18T00:24:40Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![swag\_Master](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/swag_master/32/332_2.png) [@swag\_Master](https://igraph.discourse.group/u/swag_Master)\ **Post date:** [18 August 2020 00:24 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/1 "2020-08-18T00:24:40Z")
![Screen Shot 2020-08-17 at 5.24.05 PM](https://global.discourse-cdn.com/free1/uploads/igraph/original/1X/7fd35e0e52f7fbb9355e7701bf3382836d74727f.png) Hi there! Used the Conda option for Python iGraph installation on my 64 bit Intel Mac OS. How can I fix these errors? ---
**Author:** ![vtraag](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/vtraag/32/38_2.png) [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Post date:** [20 August 2020 11:12 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/2 "2020-08-20T11:12:46Z")
Hi @swag_Master, thanks for reporting this! You mean that these errors occur when installing `igraph` using `conda`? Or did you specifically run these tests? I believe the tests are run (and pass) for linux on our [CI](https://travis-ci.org/github/igraph/python-igraph), but not for macOS, is that correct @tamas? ---
**Author:** ![tamas](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/tamas/32/1261_2.png) [@tamas](https://igraph.discourse.group/u/tamas)\ **Post date:** [22 August 2020 08:59 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/3 "2020-08-22T08:59:19Z")
We run the unit tests on macOS as well. We actually use [cibuildwheel](https://cibuildwheel.readthedocs.io) to build Python wheels for all supported architectures and Python versions, and each wheel is tested separately on its own environment, so in general it should be okay. If there is an error in the Anaconda distribution, it is something specific to Anaconda. The particular place that the error points out is a nasty hack in `igraph.Graph.Formula()` where I (ab)use Python’s own lexer to parse the “graph formulae” that `Graph.Formula()` needs as an input. I don’t think it’s harmful in the sense that it won’t affect the result / correctness of any other function from igraph. I believe I have also seen this error earlier on macOS with the “plain” system Python but I managed to do something to avoid this. (Unfortunately I can’t remember what). If I were to make a guess now, I would say it’s probably a line ending issue. We need to look into this more thoroughly. ---
**Author:** ![tamas](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/tamas/32/1261_2.png) [@tamas](https://igraph.discourse.group/u/tamas)\ **Post date:** [24 August 2020 10:53 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/4 "2020-08-24T10:53:15Z")
@vtraag Can you test this on your end a bit? I tried installing Anaconda (most recent version, with Python 3.8) on my end, but it gets stuck forever trying to resolve dependencies when installing `python-igraph`, and I have no idea what goes wrong there. ---
**Author:** ![vtraag](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/vtraag/32/38_2.png) [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Post date:** [24 August 2020 11:10 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/5 "2020-08-24T11:10:59Z")
I can take a closer look tomorrow, but I don’t have a Mac, so I unfortunately cannot test this. For the problem concerning resolving the environment, perhaps you can try to install it in a clean new environment? ---
**Author:** ![tamas](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/tamas/32/1261_2.png) [@tamas](https://igraph.discourse.group/u/tamas)\ **Post date:** [25 August 2020 15:39 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/6 "2020-08-25T15:39:42Z")
Okay, tried this in a fresh Anaconda installation in a completely clean virtualenv. This is what I got: ```auto ❯ conda install python-igraph -c conda-forge Collecting package metadata (current_repodata.json): done Solving environment: failed with initial frozen solve. Retrying with flexible solve. Solving environment: failed with repodata from current_repodata.json, will retry with next repodata source. Collecting package metadata (repodata.json): done Solving environment: failed with initial frozen solve. Retrying with flexible solve. Solving environment: - Found conflicts! Looking for incompatible packages. This can take several minutes. Press CTRL-C to abort. Examining conflict for networkx markupsafe appscript glib xlsxwriter jedi ipython pyqt partd zstd alabaster pydocstyle et_xml... ``` It then gets stuck here for at least an hour where I lost my patience and pressed Ctrl-C (this is even worse than what `pipenv` does 🙂 ). It seems to be related to `conda-forge` because it works fine with `python-igraph` from the official default channel, but that one is stuck at 0.7.1. Output of `conda info` if that helps: ```auto ❯ conda info active environment : igraph-anaconda-test active env location : /usr/local/anaconda3/envs/igraph-anaconda-test shell level : 1 user config file : /Users/tamas/.condarc populated config files : /Users/tamas/.condarc conda version : 4.8.3 conda-build version : 3.18.11 python version : 3.8.3.final.0 virtual packages : __osx=10.15.6 base environment : /usr/local/anaconda3 (writable) channel URLs : https://repo.anaconda.com/pkgs/main/osx-64 https://repo.anaconda.com/pkgs/main/noarch https://repo.anaconda.com/pkgs/r/osx-64 https://repo.anaconda.com/pkgs/r/noarch https://conda.anaconda.org/conda-forge/osx-64 https://conda.anaconda.org/conda-forge/noarch package cache : /usr/local/anaconda3/pkgs /Users/tamas/.conda/pkgs envs directories : /usr/local/anaconda3/envs /Users/tamas/.conda/envs platform : osx-64 user-agent : conda/4.8.3 requests/2.24.0 CPython/3.8.3 Darwin/19.6.0 OSX/10.15.6 UID:GID : 501:20 netrc file : /Users/tamas/.netrc offline mode : False ``` @vtraag it would be great if you could confirm whether it happens on other platforms as well. If it is macOS-specific, I’ll try to investigate further. ---
**Author:** ![vtraag](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/vtraag/32/38_2.png) [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Post date:** [25 August 2020 17:39 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/7 "2020-08-25T17:39:02Z")
To be sure, Anaconda does not work with `virtualenv` but with `conda` environments. You might want to try to install a completely clean environment and install `python-igraph` using ```nohighlight conda create -n test -c conda-forge python=3.8 python-igraph ``` This creates a new environment called `test` and works flawlessly on both Linux (Ubuntu) and Windows. You can then activate this environment using `conda activate test`. Running `python -m unittest` in the `python-igraph` source directory then also runs correctly. The tests files are not bundled with the installed package I noticed, neither for the `conda` package, nor for the `pip` wheel. ---
**Author:** ![vtraag](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/vtraag/32/38_2.png) [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Post date:** [25 August 2020 17:42 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/8 "2020-08-25T17:42:13Z")
> [@tamas](#): > > ```auto > Examining conflict for networkx markupsafe appscript glib xlsxwriter jedi ipython pyqt partd zstd alabaster pydocstyle et_xml... > > ``` I am actually not sure why these packages are included here, `networkx` is not a dependency of `python-igraph` afaik. ---
**Author:** ![tamas](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/tamas/32/1261_2.png) [@tamas](https://igraph.discourse.group/u/tamas)\ **Post date:** [25 August 2020 18:24 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/9 "2020-08-25T18:24:19Z")
> [@vtraag](#): > > To be sure, Anaconda does not work with `virtualenv` but with `conda` environments I may have used the wrong terminology, but I was using `conda` environments 😉 I’ll try again with the command line that you suggested. For what it’s worth, I’m removing the old environment now and it looks like it’s full of stuff that I never asked for but that may be present in my system Python (things like `zeromq`, `msgpack-python` and others), so that could be an explanation for why `networkx` ended up being there. ---
**Author:** ![vtraag](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/vtraag/32/38_2.png) [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Post date:** [25 August 2020 18:54 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/10 "2020-08-25T18:54:56Z")
> [@tamas](#): > > it’s full of stuff that I never asked for but that may be present in my system Python (things like `zeromq` , `msgpack-python` and others), s Some of these packages may be dependencies of other things that are installed when you create a new environment, I’m not sure. But I’m fairly sure that `networkx` should not be in there by default. Hopefully this also works correctly on macOS! ---
**Author:** ![tamas](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/tamas/32/1261_2.png) [@tamas](https://igraph.discourse.group/u/tamas)\ **Post date:** [25 August 2020 19:28 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/11 "2020-08-25T19:28:37Z")
@swag_Master Okay, I managed to install the most recent version of `python-igraph` from `conda-forge` on my machine, but I could not reproduce the error you saw there. Are you sure you have installed `python-igraph` from `conda-forge` and not from the “stock” Anaconda repo (which contains an outdated version of `python-igraph`)? You can test it by running `python -c "import igraph; print(igraph. __version__ )"` – it should print `0.8.2` and not `0.7.1` . ---
**Author:** ![vtraag](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/vtraag/32/38_2.png) [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Post date:** [25 August 2020 20:12 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/12 "2020-08-25T20:12:15Z")
> [@tamas](#): > > not from the “stock” Anaconda repo (which contains an outdated version of `python-igraph` ) I forgot to ask: where do you see this outdated version of `python-igraph`? I don’t see the `python-igraph` package at all in the default channels. Can you perhaps report how you can install the 0.7.1 version from the “stock” channel? ---
**Author:** ![tamas](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/tamas/32/1261_2.png) [@tamas](https://igraph.discourse.group/u/tamas)\ **Post date:** [25 August 2020 21:23 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/13 "2020-08-25T21:23:21Z")
To be honest, I don’t know. 🙂 Initially I typed `conda install python-igraph`, not knowing that I needed to specify `-c conda-forge` explicitly, and I somehow ended up with version 0.7.1. Hmmmm. Maybe it was also somehow pre-installed in my system Python? ---
**Author:** ![vtraag](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/vtraag/32/38_2.png) [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Post date:** [26 August 2020 07:43 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/14 "2020-08-26T07:43:02Z")
OK, I think we can then assume that people cannot install the old version 0.7.1 of `python-igraph` by accident. Then the question remains: how did the errors reported by @swag_master come about? My guess is that the files he downloaded from somewhere did indeed not have “correct” line-endings. @tamas, might it be an idea to bundle the tests with the Python package, so that the installed version can be tested somehow? Or did I miss something and are the tests already available within the Python package (i.e. not only from GitHub/source package)? ---
**Author:** ![tamas](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/tamas/32/1261_2.png) [@tamas](https://igraph.discourse.group/u/tamas)\ **Post date:** [26 August 2020 08:37 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/15 "2020-08-26T08:37:18Z")
The unit tests are included in the _source_ package (i.e. the `.tar.gz` generated by `python setup.py sdist`) but not in the _wheels_ (which most people install via `pip` nowadays). This is intentional; 99% of the users won’t need the unit tests, and if they still want them for some reason, they can always run `pip download python-igraph --no-deps --no-binary=:all:` to get the source package from the CLI. ---
**Author:** ![vtraag](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/vtraag/32/38_2.png) [@vtraag](https://igraph.discourse.group/u/vtraag)\ **Post date:** [26 August 2020 10:29 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/16 "2020-08-26T10:29:54Z")
It might still be useful for users to run tests to verify whether the installed binary version works correctly for them, no? It just adds a few kilobytes to the download (about 240Kb uncompressed, about 40Kb compressed). I don’t think that should be a problem, right? Is there any particular reason to explicitly _not_ include the unit tests? ---
**Author:** ![szhorvat](https://yyz2.discourse-cdn.com/free1/user_avatar/igraph.discourse.group/szhorvat/32/3_2.png) [@szhorvat](https://igraph.discourse.group/u/szhorvat)\ **Post date:** [26 August 2020 12:04 UTC](https://igraph.discourse.group/t/python-conda-installation-formula-errors/412/17 "2020-08-26T12:04:37Z")
> [@tamas](#): > > I may have used the wrong terminology, but I was using `conda` environments I am not fully comfortable with either Python or Anaconda, but perhaps it’s useful to state the exact commands I usually use to set this up, as they always work quickly and without issues for me (on macOS): ```auto conda create -n myenv python=3.7 conda activate myenv conda install python-igraph -c conda-forge ``` `myenv` is the environment name and 3.7 is the requested Python version.