Mesh Scale/it

import FreeCAD as App
import Mesh

# Create a non-parametric box-shaped mesh:
msh = App.ActiveDocument.addObject("Mesh::Feature", "Mesh")
msh.Mesh = Mesh.createBox(10, 10, 10)
msh.ViewObject.DisplayMode = "Flat Lines"

# Create and scale a matrix:
mat = App.Matrix()
mat.scale(2.0, 3.0, 4.0) # Unequal scaling.

# We need to work on a copy of the msh.Mesh object:
new_msh = msh.Mesh.copy()

# Transform that copy:
new_msh.transformGeometry(mat)

# Update msh.Mesh:
msh.Mesh = new_msh