Problems using embedded python package for Windows

[Rolf Fankhauser 1]

Hi all

 

I would like to deploy python with my Delphi application to my customers. So, I downloaded and installed a Windows embeddable package of Python in a subdirectory \python of my project folder.

I set the following two lines in the OnCreate event handler of the main form:

PythonEngine1.SetPythonHome('\python');
PythonEngine1.LoadDLL;

With this setting I can execute Python scripts but I cannot import numpy (ImportError: No module named 'numpy')

I can import numpy from the command line, so it seems to be correctly installed:

C:\Data\Delphi10-3\TestPythonPerformance\python>python
Python 3.5.1 (v3.5.1:37a07cee5969, Dec  6 2015, 01:38:48) [MSC v.1900 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import numpy as np
>>>

I also tested if P4D uses the correct Python distribution with:

import sys
print (sys.version)

and I get:    3.5.1 (v3.5.1:37a07cee5969, Dec  6 2015, 01:38:48) [MSC v.1900 32 bit (Intel)]

 

The structure of the Python installation is as follows (under \python):

 

Scripts
share
Lib
    site-packages
        ...
        matplotlib
        ...
        numpy
        ...
        pandas
        ...

 

Do I need to set a module path that P4D finds the modules?

 

Another problem is that importing matplotlib (even on the command line) rises an error that tkinter is not installed. If I try to install tkinter I get an error: 

ERROR: Could not find a version that satisfies the requirement tkinter (from versions: none)
ERROR: No matching distribution found for tkinter

 

Thanks, Rolf

 

 

[Rolf Fankhauser 1]

 

I used the following script (from "deploying p4d.pdf") to list the existing modules:

 

import sys
import os
print("Python path =", sys.path)
print()
print("Python modules already imported:")
for m in sys.modules.values():
    if m:
        print(" ", m)
print()
print("PYTHONHOME =", os.getenv('PYTHONHOME'))
print("PYTHONPATH =", os.getenv('PYTHONPATH'))

Output:

Python modules already imported:
  <module '_datetime' (built-in)>
  <module 'codecs' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\codecs.pyc'>
  <module 'builtins' (built-in)>
  <module 'encodings.aliases' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\encodings\\aliases.pyc'>
  <module '_frozen_importlib_external' (frozen)>
  <module 'io' (built-in)>
  <module 'time' (built-in)>
  <module 'encodings.mbcs' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\encodings\\mbcs.pyc'>
  <module 'genericpath' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\genericpath.pyc'>
  <module '_collections_abc' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\_collections_abc.pyc'>
  <module 'marshal' (built-in)>
  <module 'sys' (built-in)>
  <module '_weakrefset' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\_weakrefset.pyc'>
  <module 'zlib' (built-in)>
  <module 'os' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\os.pyc'>
  <module 'ntpath' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\ntpath.pyc'>
  <module 'stat' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\stat.pyc'>
  <module 'encodings' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\encodings\\__init__.pyc'>
  <module '_bootlocale' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\_bootlocale.pyc'>
  <module 'ntpath' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\ntpath.pyc'>
  <module '_weakref' (built-in)>
  <module 'encodings.latin_1' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\encodings\\latin_1.pyc'>
  <module 'abc' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\abc.pyc'>
  <module 'errno' (built-in)>
  <module 'site' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\site.pyc'>
  <module '_codecs' (built-in)>
  <module '_sitebuiltins' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\_sitebuiltins.pyc'>
  <module 'zipimport' (built-in)>
  <module '_thread' (built-in)>
  <module '_frozen_importlib' (frozen)>
  <module '_signal' (built-in)>
  <module '_locale' (built-in)>
  <module 'encodings.utf_8' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\encodings\\utf_8.pyc'>
  <module 'winreg' (built-in)>
  <module 'sysconfig' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\sysconfig.pyc'>
  <module 'math' (built-in)>
  <module 'pyio'>
  <module 'nt' (built-in)>
  <module '_stat' (built-in)>
  <module '_imp' (built-in)>
  <module '_warnings' (built-in)>
  <module 'datetime' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\datetime.pyc'>
  <module '__main__' (built-in)>
  <module 'io' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\io.pyc'>
  <module 'encodings.cp1252' from 'C:\\Data\\Delphi10-3\\TestPythonPerformance\\python\\python35.zip\\encodings\\cp1252.pyc'>

PYTHONHOME = None
PYTHONPATH = None

It seems that only modules in python35.zip are imported

[SwiftExpat 65]

Hello Rolf,

 

There is a file in the directory with the suffix, should be python35._pth that needs to be modified to import site.

 

Here are the references I used to get past the issue:

https://dev.to/fpim/setting-up-python-s-windows-embeddable-distribution-properly-1081

https://www.christhoung.com/2018/07/15/embedded-python-windows/

[Rolf Fankhauser 1]

Hello SwiftExpat

 

Thanks for the links. I already know the first link. The problem is that I have no such file python35._pth.

I will check the other link and possibly download and install the embeddable distribution again.

[Rolf Fankhauser 1]

I now installed the newest version with python 3.9.4. There is a file python39._pth

(I checked it: Indeed, the python35 package didn't have a file python35._pth)

So, I changed all according to the instructions.

I installed numpy and matplotlib but when I try matplotlib from the command prompt and want to plot I get the following warning:

 UserWarning: Matplotlib is currently using agg, which is a non-GUI backend, so cannot show the figure.

Only this backend "agg" is installed, no others.

If I try to install Tkinter I get the same error as before with the python35 package: 

ERROR: Could not find a version that satisfies the requirement Tkinter
ERROR: No matching distribution found for Tkinter

Can I use a Delphi window as backend?

Saving the plot as png or svg and display it in Delphi would be a workaround but rather complicated.

[Rolf Fankhauser 1]

I installed the PyQt5 package:

...\python> cd Scripts

...\python\Scripts> pip install PyQt5

 

Now matplotlib is working with GUI because there is now Qt as a GUI backend. The window doesn't look really native, Tk looks nicer.