从脚本（a.py）导入python模块/站点包（例如scipy），但不能从tkinter button命令导入

Question

Importing a python site-package (eg 'scipy') works fine from a script test.py, but not from tkinter button command. When click the button, error shows：

ModuleNotFoundError: No module named 'scipy'

test.py

import scipy
print ("hello world")

GUI.py

import sys
import os
import tkinter
top=tkinter.Tk()

def startCamera():
    os.system('python test.py')

B=tkinter.Button(top,text="hello",command= startCamera)
B.pack()
top.mainloop()

Both the test.py and GUI.py are in a same folder: C:\\Users\\Breda\\PycharmProjects\\face_reg\\face

scipy package in: C:\\Users\\Breda\\Anaconda3\\Lib\\site-packages

sys.path variable contains: C:\\Users\\Breda\\Anaconda3\\Lib\\site-packages

I tried to import other site-packages in test.py and run via GUI button command , all face the same problem. Any ideas?

Answer 1

The reason why the scipy module could not be found is because the python executable run by os.system was not part of the python installation which had scipy installed. (There is more than one python distribution installed on this machine.)

The issue was diagnosed by putting

import sys
print(sys.executable)

at the top of the test.py file (before import scipy ). This prints the path to the python executable. Then test.py was run twice -- once from the command-line, and once through GUI.py . The two test runs printed different paths.

The problem was fixed by setting Pycharm's default python executable to the Anaconda Python3 installation which has the scipy module installed.