Is there a way to call a Python code in Excel-VBA?
There are multiple ways tu run a python script with VBA depending on whether you need to wait for the end of the execution and know if it went without error.
With Shell, asynchronous with console:
Public Sub RunPython(file As String, ParamArray args())
Shell "python.exe """ & file & """ " & Join(args, " ")
End Sub
With Shell, synchronous without console:
Public Function RunPython(file As String, ParamArray args())
Shell "pythonw.exe """ & file & """ " & Join(args, " ")
End Function
With WScript.Shell, synchronous without console and with exit code:
Public Function RunPython(file As String, ParamArray args()) As Long
Dim obj As Object
Set obj = CreateObject("WScript.Shell")
RunPython = obj.Run("pythonw.exe """ & file & """ " & Join(args, " "), 0, True)
End Function
Yes, there is. My preferred way of doing this is through xlwings (https://www.xlwings.org/), but there are several other options as well. XlWings is great because it's free, open source and easy to use, with great documentation. There are some feature limitations though, so you'd have to check if it fits your needs.
The simplest way is to run the python interpreter with the Shell
command
Shell ("python.exe " & yourScript & " " & arguments)
I had a whole Python month on my blog right here. I establish a pattern which I call the gateway class which is a COM enabled Python class, it will register itself if run from the command line and once registered is instantiated with CreateObject("foo.bar").
Here is a good example of VBA calling a Python class that uses some scipy functions
import numpy as np
import pandas as pd
from scipy.stats import skewnorm
class PythonSkewedNormal(object):
_reg_clsid_ = "{1583241D-27EA-4A01-ACFB-4905810F6B98}"
_reg_progid_ = 'SciPyInVBA.PythonSkewedNormal'
_public_methods_ = ['GeneratePopulation', 'BinnedSkewedNormal']
def GeneratePopulation(self, a, sz):
# https://docs.scipy.org/doc/numpy-1.15.1/reference/generated/numpy.random.seed.html
np.random.seed(10)
# https://docs.scipy.org/doc/scipy-0.19.1/reference/generated/scipy.stats.skewnorm.html
return skewnorm.rvs(a, size=sz).tolist()
def BinnedSkewedNormal(self, a, sz, bins):
# https://docs.scipy.org/doc/numpy-1.15.1/reference/generated/numpy.random.seed.html
np.random.seed(10)
# https://docs.scipy.org/doc/scipy-0.19.1/reference/generated/scipy.stats.skewnorm.html
pop = skewnorm.rvs(a, size=sz)
bins2 = np.array(bins)
bins3 = pd.cut(pop, bins2)
table = pd.value_counts(bins3, sort=False)
table.index = table.index.astype(str)
return table.reset_index().values.tolist()
if __name__ == '__main__':
print("Registering COM server...")
import win32com.server.register
win32com.server.register.UseCommandLine(PythonSkewedNormal)
and the calling VBA code
Option Explicit
Sub TestPythonSkewedNormal()
Dim skewedNormal As Object
Set skewedNormal = CreateObject("SciPyInVBA.PythonSkewedNormal")
Dim lSize As Long
lSize = 100
Dim shtData As Excel.Worksheet
Set shtData = ThisWorkbook.Worksheets.Item("Sheet3") '<--- change sheet to your circumstances
shtData.Cells.Clear
Dim vBins
vBins = Array(-5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5)
'Stop
Dim vBinnedData
vBinnedData = skewedNormal.BinnedSkewedNormal(-5, lSize, vBins)
Dim rngData As Excel.Range
Set rngData = shtData.Cells(2, 1).Resize(UBound(vBins) - LBound(vBins), 2)
rngData.Value2 = vBinnedData
'Stop
End Sub
Full commentary can be found at the original blog entry here
The advantage here is that there is no shelling. When the code it returns, you know it has finished, with shelling once has to check if the shelled process has ended etc. This gateway class is much better IMHO.