Set ENV["PYTHON"]="pythoncommand"

I just installed Python3 from the installer at my Windows 10 device, and got this error while trying Pkg.add("PyPlot")

In my Mac I also installed python3 from the installer, and got the same error

┌ Error: Error building `PyCall`: 
│ ┌ Info: Using the Python distribution in the Conda package by default.
│ └ To use a different Python version, set ENV["PYTHON"]="pythoncommand" and re-run Pkg.build("PyCall").

In the terminal I tried:

set ENV["PYTHON"]="python3"

But did not work, it looks I did not understood the note.

I read some topics of the recommendations appeared while writing this, but did not get exact issue!

1 Like

Did you set ENV["PYTHON"] in the Julia session before you ran ]build PyCall?

Can you also do which python3 and ensure it returns and non-empty string from a fresh terminal session?

I think this what I did not understood, put what and where, what shall I write and where?

Oh, sorry I just realized that you said you did that in the terminal.

In Julia, ENV is a global dictionary that stores the current environment. Take a look at it by typing ENV in the REPL. What the PyCall install is asking you to do is to set ENV["PYTHON"] = "/path/to/python/binary" in Julia before you call ]build PyCall.

3 Likes

Thanks, I got the path in Mac using below at terminal:

 $ which python3

Then in Julia REPL I wrote:

ENV["PYTHON"]="/Library/Frameworks/Python.framework/Versions/3.7/bin/python3"

Then run in the REPLT

Pkg.build("PyCall")

Then I got this error:

ERROR: LoadError: InitError: PyCall.PyError("PyImport_ImportModule\n\nThe Python package matplotlib could not be found by pyimport. Usually this means\nthat you did not install matplotlib in the Python version being used by PyCall.\n\nPyCall is currently configured to use the Python version at:\n\n/Library/Frameworks/Python.framework/Versions/3.7/bin/python3\n\nand you should use whatever mechanism you usually use (apt-get, pip, conda,\netcetera) to install the Python package containing the matplotlib module

So, I install matplot in the terminalas:

$ pip3 install matplotlib

Then I forced to do recompiling for Pkg.add("PyPlot"), to get it done.

Now below code works fine at jupyter lab

Pkg.add("Plots")
Pkg.add("Measures")
Pkg.add("PyPlot")
println("hello from Julia function")
using Plots, Measures
pyplot()

data = [rand(100), rand(100)];

h = histogram(data, layout = 2,
              title = ["Dataset A" "Dataset B"], legend = false,
              ylabel = "ylabel", margin = 5mm)
display(h)

In Windows 10 the path was

ENV["PYTHON"]="C:/Program Files (x86)/Python37-32/python"

But while executing Pkg.build("PyCall") I got an error:

┌ Error: Error building `PyCall`: 
│ ┌ Info: No system-wide Python was found; got the following error:
│ │ ErrorException("C:/Program Files (x86)/Python37-32/python is 32-bit, but Julia is 64-bit")
│ └ using the Python distribution in the Conda package

So, I got forced to remove the 32bit edition of Python3, and install the 64bit edition and fixed the ENV in the ``REPL` as:

ENV["PYTHON"]="C:/Program Files/Python37/python"

And faced in Windows this error:

LoadError: FFMPEG not installed properly

So I downloaded the build from here, unzipped it, and added it to the path.

Thanks

2 Likes

Hello everyone,

I’ve been having a similar issue; found several threads on the matter but still haven’t been able to figure it out.

This is the error message I get:

    Building PyCall → `C:\Users\Lali\.julia\scratchspaces\44cfe95a-1eb2-52ea-b672-e2afdf69b78f\4ba3651d33ef76e24fef6a598b63ffd1c5e1cd17\build.log`
ERROR: Error building `PyCall`:
┌ Info: Using the Python distribution in the Conda package by default.
└ To use a different Python version, set ENV["PYTHON"]="pythoncommand" and re-run Pkg.build("PyCall").
[ Info: Running `conda install -y numpy` in root environment
ERROR: LoadError: failed process: Process(setenv(`'C:\Users\Lali\.julia\conda\3\Scripts\conda.exe' install -y numpy`,["PATH=C:\\Users\\Lali\\.julia\\conda\\3\\Library\\bin;C:\\Program Files (x86)\\Common Files\\Oracle\\Java\\javapath;C:\\Program Files (x86)\\Intel\\iCLS Client\\;C:\\Program Files\\Intel\\iCLS Client\\;C:\\Windows\\system32;C:\\Windows;C:\\Windows\\System32\\Wbem;C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\;C:\\Program Files\\Intel\\Intel(R) Management Engine Components\\DAL;C:\\Program Files (x86)\\Intel\\Intel(R) Management Engine Components\\DAL;C:\\Program Files\\Intel\\Intel(R) Management Engine Components\\IPT;C:\\Program Files (x86)\\Intel\\Intel(R) Management Engine Components\\IPT;C:\\Program Files\\MATLAB\\runtime\\win64;C:\\Program Files\\MATLAB\\bin;C:\\Program Files\\Polyspace\\R2021a\\runtime\\win64;C:\\Program Files\\Polyspace\\R2021a\\bin;C:\\Program Files\\MATLAB\\R2019a\\runtime\\win64;C:\\Program Files\\MATLAB\\R2019a\\bin;C:\\Program Files\\MATLAB\\R2018a\\runtime\\win64;C:\\Program Files\\MATLAB\\R2018a\\bin;C:\\Program Files (x86)\\MATLAB\\MATLAB Compiler Runtime\\v713\\runtime\\win32;C:\\Program Files\\Common Files\\Autodesk Shared\\;C:\\Program Files\\MATLAB\\polyspace\\bin;C:\\Program Files\\MATLAB\\MATLAB Runtime\\v901\\runtime\\win64;C:\\Program Files\\MiKTeX 2.9\\miktex\\bin\\x64\\;C:\\Program Files (x86)\\Wolfram Research\\WolframScript\\;C:\\Program Files\\MATLAB\\R2019a\\polyspace\\bin;C:\\Julia-1.5.0\\bin;C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\;C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\;C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\;C:\\Julia-1.5.0\\bin;C:\\Program Files\\NVIDIA Corporation\\NVIDIA NvDLISR;C:\\Program Files (x86)\\NVIDIA Corporation\\PhysX\\Common;C:\\Program Files\\Polyspace\\R2021a\\polyspace\\bin;C:\\Users\\Lali\\AppData\\Local\\atom\\bin;C:\\Julia-1.6.3\\bin", "HOMEPATH=\\Users\\Lali", "PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC", "NODE_ENV=production", "SESSIONNAME=Console", "SYSTEMROOT=C:\\Windows", "APPDATA=C:\\Users\\Lali\\AppData\\Roaming", "PSMODULEPATH=C:\\Windows\\system32\\WindowsPowerShell\\v1.0\\Modules\\", "COMMONPROGRAMW6432=C:\\Program Files\\Common Files", "PROGRAMDATA=C:\\ProgramData"  …  "CHROME_CRASHPAD_PIPE_NAME=\\\\.\\pipe\\crashpad_7488_APRVFBOJAOFUAMQU", "LOGONSERVER=\\\\POLYMOD", "ORIGINAL_XDG_CURRENT_DESKTOP=undefined", "ILMDIR=C:\\Program Files (x86)\\Common Files\\Autodesk Shared\\Materials\\", "CONDA_PREFIX=C:\\Users\\Lali\\.julia\\conda\\3", "ATOM_HOME=C:\\Users\\Lali\\.atom", "JULIA_LOAD_PATH=@;C:\\Users\\Lali\\AppData\\Local\\Temp\\jl_GsxjSn", "SYSTEMDRIVE=C:", "PROCESSOR_ARCHITECTURE=AMD64", "OPENBLAS_MAIN_FREE=1"]), ProcessExited(3221225595)) [3221225595]

Stacktrace:
 [1] pipeline_error
   @ .\process.jl:525 [inlined]
 [2] run(::Cmd; wait::Bool)
   @ Base .\process.jl:440
 [3] run
   @ .\process.jl:438 [inlined]
 [4] runconda(args::Cmd, env::String)
   @ Conda C:\Users\Lali\.julia\packages\Conda\sNGum\src\Conda.jl:129
 [5] add(pkg::String, env::String; channel::String)
   @ Conda C:\Users\Lali\.julia\packages\Conda\sNGum\src\Conda.jl:221
 [6] add (repeats 2 times)
   @ C:\Users\Lali\.julia\packages\Conda\sNGum\src\Conda.jl:220 [inlined]
 [7] top-level scope
   @ C:\Users\Lali\.julia\packages\PyCall\3fwVL\deps\build.jl:79
 [8] include(fname::String)
   @ Base.MainInclude .\client.jl:444
 [9] top-level scope
   @ none:5
in expression starting at C:\Users\Lali\.julia\packages\PyCall\3fwVL\deps\build.jl:43
Stacktrace:
  [1] pkgerror(msg::String)
    @ Pkg.Types C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\Types.jl:55
  [2] (::Pkg.Operations.var"#82#87"{Bool, Pkg.Types.Context, String, Pkg.Types.PackageSpec})()
    @ Pkg.Operations C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\Operations.jl:1048
  [3] withenv(::Pkg.Operations.var"#82#87"{Bool, Pkg.Types.Context, String, Pkg.Types.PackageSpec}, ::Pair{String, String}, ::Vararg{Pair{String, B} where B, N} where N)
    @ Base .\env.jl:161
  [4] (::Pkg.Operations.var"#109#113"{String, Pkg.Operations.var"#82#87"{Bool, Pkg.Types.Context, String, Pkg.Types.PackageSpec}, Pkg.Types.PackageSpec})()
    @ Pkg.Operations C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\Operations.jl:1546
  [5] with_temp_env(fn::Pkg.Operations.var"#109#113"{String, Pkg.Operations.var"#82#87"{Bool, Pkg.Types.Context, String, Pkg.Types.PackageSpec}, Pkg.Types.PackageSpec}, temp_env::String)
    @ Pkg.Operations C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\Operations.jl:1448
  [6] (::Pkg.Operations.var"#108#112"{Pkg.Operations.var"#82#87"{Bool, Pkg.Types.Context, String, Pkg.Types.PackageSpec}, Pkg.Types.Context, Pkg.Types.PackageSpec, String, Pkg.Types.Project, String})(tmp::String)
    @ Pkg.Operations C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\Operations.jl:1521
  [7] mktempdir(fn::Pkg.Operations.var"#108#112"{Pkg.Operations.var"#82#87"{Bool, Pkg.Types.Context, String, Pkg.Types.PackageSpec}, Pkg.Types.Context, Pkg.Types.PackageSpec, String, Pkg.Types.Project, String}, parent::String; prefix::String)
    @ Base.Filesystem .\file.jl:729
  [8] mktempdir(fn::Function, parent::String) (repeats 2 times)
    @ Base.Filesystem .\file.jl:727
  [9] sandbox(fn::Function, ctx::Pkg.Types.Context, target::Pkg.Types.PackageSpec, target_path::String, sandbox_path::String, sandbox_project_override::Pkg.Types.Project)
    @ Pkg.Operations C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\Operations.jl:1487
 [10] build_versions(ctx::Pkg.Types.Context, uuids::Vector{Base.UUID}; verbose::Bool)
    @ Pkg.Operations C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\Operations.jl:1029
 [11] build(ctx::Pkg.Types.Context, pkgs::Vector{Pkg.Types.PackageSpec}, verbose::Bool)
    @ Pkg.Operations C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\Operations.jl:910
 [12] build(ctx::Pkg.Types.Context, pkgs::Vector{Pkg.Types.PackageSpec}; verbose::Bool, kwargs::Base.Iterators.Pairs{Symbol, Base.TTY, Tuple{Symbol}, NamedTuple{(:io,), Tuple{Base.TTY}}})
    @ Pkg.API C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\API.jl:900
 [13] build(pkgs::Vector{Pkg.Types.PackageSpec}; io::Base.TTY, kwargs::Base.Iterators.Pairs{Union{}, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ Pkg.API C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\API.jl:80
 [14] build(pkgs::Vector{Pkg.Types.PackageSpec})
    @ Pkg.API C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\API.jl:78
 [15] #build#71
    @ C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\API.jl:76 [inlined]
 [16] build
    @ C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\API.jl:76 [inlined]
 [17] #build#70
    @ C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\API.jl:75 [inlined]
 [18] build(pkg::String)
    @ Pkg.API C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\Pkg\src\API.jl:75
 [19] top-level scope
    @ none:1

Any ideas? I’m using Julia v 1.6.3 (2021-09-23) on Atom.

Thanks a lot!

Try

ENV["PYTHON"]=""

What happens if you try running C:\Users\Lali\.julia\conda\3\Scripts\conda.exe from your OS terminal?

(If your Conda installation is corrupted somehow, you could delete the C:\Users\Lali\.julia\conda directory and try again.)