create delphi4python at run time, extend demo sample 34

Edited March 14, 2021 by FranzB

pyscripter · March 15, 2021

Regarding numpy on Linux if you use the default python 3 installation it would suffice to install numpy via pip:

pip3 install numpy

FranzB · March 16, 2021

yes , here comes a numpy short demo on windows .... execution is perfect

I installed numpy via pip , did not need to set a DLL path

see screen dump

(on LINUX i don't have admin rights to install software using pip, will report results later - need other LINUX computer )

#  demo script
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(0,8*np.pi,0.1)   # start,stop,step
y = np.cos(x) *1/(1+x)
plt.plot(x,y)
plt.show()

Edited March 16, 2021 by FranzB

FranzB · March 16, 2021

I still need a helping hand on one failure of the demo34Extend sample :

Q : why is python text output not written to the output memo in Delphi app, python engine for sure is running, see post above

procedure TForm_P4Deval.btn_CreatePythonEnviromentClick(Sender: TObject);

begin

  //  run this function prior to execute python code

  FPythonEngine := TPythonEngine.Create(nil);
  FPythonInOut := TPythonInputOutput.Create(nil);


  try

    FPythonInOut.UnicodeIO := True;
    FPythonInOut.RawOutput := True;
    FPythonInOut.OnSendUniData := PythonInputOutputSendUniData;


{$IFDEF  MSWINDOWS}
    FPyVersions := GetRegisteredPythonVersions;
    FPyVersions[0].AssignTo(FPythonEngine);
{$ENDIF}

    FPythonEngineConfig.SetPythonengineValues(FPythonEngine);

    FPythonEngine.Loaddll;
    FPythonEngine.IO := FPythonInOut;



    { TPythonModule }
    FPythonModule1 := TPythonModule.Create(Self);

    FPythonModule1.Name := 'PythonModule1';
    FPythonModule1.Engine := FPythonEngine;
    FPythonModule1.ModuleName := 'spam';
    with FPythonModule1.Errors.Add do
    begin
      Name := 'PointError';
      ErrorType := etClass;
    end;
    with FPythonModule1.Errors.Add do
    begin
      Name := 'EBadPoint';
      ErrorType := etClass;
      ParentClass.Name := 'PointError';
    end;

  except
    on E: Exception do
      writeln(E.ClassName, ': ', E.Message);

  end;
end;

procedure TForm_P4Deval.btn_FreePythonEnviromentClick(Sender: TObject);
begin

  FPythonEngine.Free;
  FPythonInOut.Free;

end;

Config_windows.ini

Edited March 16, 2021 by FranzB
add source files again

pyscripter · March 16, 2021

Can't you debug? Is PythonInputOutputSendUniData called? If yes why it does not produce output?

pyscripter · March 16, 2021

@FranzBHave you tried debugging?

Edited March 16, 2021 by pyscripter

FranzB · March 16, 2021

yes, tried debugging

function TForm_P4Deval.PythonInputOutputSendUniData(Sender: TObject); is never called , even I assigned this function during the create components function

for data output.

I'm using FMX framework and lastest Delphi 10.4.2 , full working code is attached below

    FPythonInOut.UnicodeIO := True;
    FPythonInOut.RawOutput := True;
    FPythonInOut.OnSendUniData := PythonInputOutputSendUniData;


{$IFDEF  MSWINDOWS}
    FPyVersions := GetRegisteredPythonVersions;
    FPyVersions[0].AssignTo(FPythonEngine);
{$ENDIF}

    FPythonEngineConfig.SetPythonengineValues(FPythonEngine);

    FPythonEngine.Loaddll;
    FPythonEngine.IO := FPythonInOut;

Config_windows.ini

Edited March 16, 2021 by FranzB

Joseph MItzen · March 16, 2021

20 hours ago, pyscripter said:

Regarding numpy on Linux if you use the default python 3 installation it would suffice to install numpy via pip:

pip3 install numpy

If you're using the version of Python bundled with your Linux distro, you should either install NumPy from the Linux distro's package manager, use the "--user" option to install the package in the user's home directory (making sure the path is adjusted accordingly) or install into a virtual environment. Otherwise you could have problems with the distro package manager and pip conflicting. The distro package manager won't know pip installed NumPy to the system directory and could end up overwriting it in the future during an install or update.

pyscripter · March 16, 2021

@FranzB

Your need to assign the IO before loading the python dll. Otherwise the output is not redirected.

    FPythonEngine.IO := FPythonInOut;
    FPythonEngine.Loaddll;

FranzB · March 17, 2021

good news : changed the code according your help and also created new *.ini file -> text is written to output file now 🙂

bad news : its difficult to find the correct parameter settings on a client computer system - there are to many options where python might be installed ...... https://github.com/pyscripter/python4delphi/wiki/FindingPython

action : improve finding and setting of correct parameters ..... otherwise an app won't run on a different computer

procedure TPythonEngineConfig.SetPythonengineValues(PythonEngine
  : TPythonEngine);
var
  FPyVersions: TPythonVersions;
begin
  ///
  /// convert this  https://github.com/pyscripter/python4delphi/wiki/FindingPython
  /// into a small  automatic setting  of parameter
  ///
  PythonEngine.UseLastKnownVersion := Self.UseLastKnownVersion;
  if Self.UseLastKnownVersion then
  begin
{$IFDEF  MSWINDOWS}
    FPyVersions := GetRegisteredPythonVersions;
    FPyVersions[0].AssignTo(PythonEngine);
{$ENDIF}
{$IFDEF  LINUX}
    /// see https://en.delphipraxis.net/topic/4700-getregisteredpythonversions-for-linux/
{$ENDIF}
  end
  else
  begin
    PythonEngine.DllName := Self.DllName;
    PythonEngine.DllPath := Self.DllPath;
    PythonEngine.AutoFinalize := Self.AutoFinalize;
    PythonEngine.AutoLoad := Self.AutoLoad;
    PythonEngine.AutoUnload := Self.AutoUnload;
    PythonEngine.RedirectIO := Self.RedirectIO;
    PythonEngine.UseWindowsConsole := Self.UseWindowsConsole;
  end;
end;

demo project :