How can i take the x, y, and z of the axis by a part object in python?

[frmgr]

myCylinder = FreeCAD.ActiveDocument.getObject("Cylinder")
yc = float (myCylinder.Placement.Base.y)

I use this code to take the y value of the position. How can i do to take the value of the y of the axis?


(version 0.20.1 windows)

[chrisb]

I may not understand: The origin of a cylinder is on the axis. Getting the y value of the cylinder gives you the y value of the axis.

[frmgr]

Sorry, I badly explayned myself: i need to import the rotation axis (i don't know the exact name, but is the one in the attached image)

[edwilliams16]

Code: Select all

myCylinder.Placement.Rotation.Axis.y

though it isn't clear what purpose you might have for a single component of the Axis vector. Most applications would require the entire vector.

[frmgr]

thank you, that was what i needed

[wmayer]

Code: Select all

myCylinder.Placement.Rotation.RawAxis.y

There is a slight difference between Axis and RawAxis. The former always is a normalized vector so that you usually get a different value than shown in the property editor.

If you change x and y of the axis to -1 in the property editor then

Code: Select all

myCylinder.Placement.Rotation.Axis.y

returns -0.7071067811865475 (i.e. -sqrt(0.5)) while

Code: Select all

myCylinder.Placement.Rotation.RawAxis.y

still returns -1.