# Relative pose in 2D: problem 1

sky on 14 Jan 2024
Latest activity Reply by Dyuman Joshi on 18 Jan 2024

I'm having problem in its test 6 ... passing 5/6 what would be the real issue..
am wring Transformation matrix correct.. as question said SSW should be 202.5 degree...
so what is the issue..

Dyuman Joshi on 17 Jan 2024
Given that the frame of reference is a cartesian co-ordinate system, the angle is supposed/expected to be calculated w.r.t x-axis CCW.
For that, SSW would be 247.5 degrees (180+45+45/2 degrees)
Dyuman Joshi on 18 Jan 2024
Yes, I am aware of the popular notation.
I am trying to justify/explain the value used by OOP with regard to their question.
I will edit my answer to elaborate further.
Cris LaPierre on 18 Jan 2024
SSW is much more commonly used to indicate a cardinal or geographic axis, where degrees increase in a CW manner from N. Searching online for SSW in degrees will indicate 202.5 degrees. The OP's confusion is understandable.
Dyuman Joshi on 18 Jan 2024
@Cris LaPierre, in cartesian coordinates (as is the case in the question), the angle is measured from the x-axis in CCW direction.
In accordance to that, SSW is 247.5 degrees and WSW is 202.5 degrees.
Cris LaPierre on 17 Jan 2024
247.5 is WSW
Dyuman Joshi on 17 Jan 2024
Note - This is a question regarding this particular Cody problem - https://in.mathworks.com/matlabcentral/cody/problems/44819-relative-pose-in-2d-problem-1