@sam wrote:
in PositionMatrix translation I have no clue where Length (106.0666) is coming from.
The length is expected for the values of X, Y, and Z. You can think of the length as the distance from (0, 0, 0) to (75, -75, 0). By pythagorean theorem this is sqrt(75^2+75^2)=106.066, so my math agrees with Inventor's.
@sam wrote:
X is fine though it should show 75 instead of 74.99999
This can come from a number of places... floating point binary representations of numbers are imperfect and lead to rounding errors, some of which are not exactly obvious. For example in base 10 we know that some numbers do not have exact representations--for example 1/3 = 0.333... and there is no way to exactly represent this number as a decimal. With binary representations, 1/10 suffers from the same problem--it is a repeating decimal with no exact representation. As a result of this (and other oddities of binary floating point math), you will often see rounding errors that you might not expect. Well written software usually tries to hide this weirdness from the user, but since you are in API land, none of this will be hidden from you.
@sam wrote:
again I don't know where -75 is coming from as Y-axis value.
Have a look at this excellent document (handout from Brian Ekins' 2008 AU presentation How Deep is the Rabbit Hole?) https://modthemachine.typepad.com/files/mathgeometry.pdf
If you read the document and still have questions, I suggest sharing your code. There is very little I can do to help with just a screenshot of a couple lines.