Run Python with package NumPy in Mathematica

Question

For example, if I have a Python script called simple.py that contains code as simple as

a=1
print(a)

then

RunProcess[{"python", "E:wsimple.py"}]

is OK and gives

<|"ExitCode" -> 0, "StandardOutput" -> "1

  ", "StandardError" -> ""|>

However, if I edit simple.py as

import numpy as np
a=np.array([1,2])
print(a)

then

RunProcess[{"python", "E:wsimple.py"}]

gives

<|"ExitCode" -> 1, "StandardOutput" -> "",
 "StandardError" -> "Traceback (most recent call last):

    File "E:wWORKpythonlearningsimple.py", line 1, in 
<module>

      import numpy as np

    File "D:IntelPython35libsite-packagesnumpy__init__.py"
, line 158, in <module>

      from . import add_newdocs

    File "D:IntelPython35libsite-packagesnumpyadd_newdocs.
py", line 13, in <module>

      from numpy.lib import add_newdoc

    File "D:IntelPython35libsite-packagesnumpylib__init__
.py", line 8, in <module>

      from .type_check import *

    File "D:IntelPython35libsite-packagesnumpylibtype_
check.py", line 11, in <module>

      import numpy.core.numeric as _nx

    File "D:IntelPython35libsite-packagesnumpycore__init_
_.py", line 21, in <module>

      from . import umath

  ImportError: DLL load failed: ÕÒ.b2»[Micro]½Ö¸[Paragraph]¨
[Micro]Ä.b3ÌÐò¡£

  "|>

What is wrong? How can I make NumPy work with RunProcess?

Update

I’ve tried on a Linux computer. The same Python script works. So is it a problem of why RunProcess doesn’t import packages correctly on Windows?

Update

A workaround.

I uninstalled Intel Python and install Anaconda.

Now it is working. Maybe Intel Python misses something in the PATH.

python

b3m2a1 · Answer

I don't know how to resolve your issue, but here are my two cents.

I think it's likely a process environment issue as this works for me on Mac with Mathematica 11.1:

RunProcess[{"python3.4", "-i"},
 "StandardOutput",
 "import numpy as np; a=np.array([1,2]); print(a)",
 ProcessEnvironment ->
  <|
   "PATH" -> "/usr/local/bin:" <> Environment["PATH"]
   |>
 ]

"[1 2]
"

The different ProcessEnvironment is something I always need to run python, since I never bother to use SetEnvironment

LouisB · Answer

I installed IntelPython3 on Windows 7 and this worked (with Mathematica 10.1) for me:
SetDirectory["UsersgaussDocumentsPython Scripts"]
RunProcess[{"C:IntelPython3python.exe", "simple.py"}]

It worked without any adjustment to paths or environment variables.  It also worked without the ".exe" file extension, but it did not work without the "C:".
The SetDirectory was only necessary because I used the filename "simple.py".  It is also possible to use a relative pathname without SetDirectory.  That is, this also worked for me as the first command after launching Mathematica:
RunProcess[{"C:IntelPython3python.exe", "Python Scriptssimple.py"}]

In both cases, Python was able to import the NumPy package, create the array and produce the proper output.
Mathematica environment:
When I wrote in the above that it did not work, I should have said the problem was a Mathematica "file not found" error, not a Python message saying that NumPy could not be imported.  Here is the environment information you requested:
StringSplit[Environment["PATH"], ";"] // Column
(*

"C:Program FilesWolfram 
ResearchMathematica10.1SystemFilesLibrariesWindows-x86-64",
 "C:Program FilesWolfram 
ResearchMathematica10.1SystemFilesLibrariesWindows",
 "C:Program FilesWolfram 
ResearchMathematica10.1SystemFilesKernelBinariesWindows-
x86-64",
 "C:Program FilesWolfram ResearchMathematica10.1",
 "C:Program FilesWolfram 
ResearchMathematica10.1SystemFilesFrontEndBinariesWindows-
x86-64",
 "C:Program FilesWolfram 
ResearchMathematica10.1SystemFilesKernelBinariesWindows-
x86-64",
 "C:Windowssystem32",
 "C:Windows",
 "C:WindowsSystem32Wbem",
 "C:WindowsSystem32WindowsPowerShellv1.0"

*)

My Python file
I added code to the Python script to print the environment variable PATH, so here is my script:

try :
      import os
      print(os.environ["PATH"])
    except :
      print("no import os, or no PATH")
    try :
      import numpy as np
      b = np.array([1,2,3])
      print(b)
    except :
      a = "jello world"
      print(a)

Mathematica evaluation
You will note that IntelPython3 has added two path elements at the beginning of the path:
RunProcess[{"C:IntelPython3python.exe", "Python Scriptssimple.py"}]
(*
<|"ExitCode" -> 0,
 "StandardOutput" ->
  "C:IntelPython3Librarybin;C:IntelPython3DLLs;C:Program 
FilesWolfram 
ResearchMathematica10.1SystemFilesLibrariesWindows-x86-64;C:
Program FilesWolfram 
ResearchMathematica10.1SystemFilesLibrariesWindows;C:
Program FilesWolfram 
ResearchMathematica10.1SystemFilesKernelBinariesWindows-
x86-64;C:Program FilesWolfram 
ResearchMathematica10.1;C:Program FilesWolfram 
ResearchMathematica10.1SystemFilesFrontEndBinariesWindows-
x86-64;C:Program FilesWolfram 
ResearchMathematica10.1SystemFilesKernelBinariesWindows-
x86-64;C:Windowssystem32;C:Windows;C:WindowsSystem32Wbem;
C:WindowsSystem32WindowsPowerShellv1.0

[1 2 3]

", "StandardError" -> ""|>
*)

Edmund · Answer

Starting in version 11.2 you may use ExternalEvaluate to run Python from Mathematica.  See the Configure Python for ExternalEvaluate tutorial for setup.

session = StartExternalSession[<|"System" -> "Python", "ReturnType" -> "Expression"|>]

Then

res = ExternalEvaluate[session, 
  "import numpy as np; a=np.array([1,2]); a.tolist()"]

{1, 2}

End the session with the following.

DeleteObject@session

Hope this helps.

Run Python with package NumPy in Mathematica

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