Polar coordinates of image.

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Stewart Tan
Stewart Tan on 6 Sep 2019
Commented: Walter Roberson on 7 Sep 2019
So i have used the cart2pol() function to obtain the polar coordinates represented by and θ. In a paper I'm analysing, it is said that the image function, will be multiplied with a matrix.
Is it possible to use in Matlab instead of the normal ?

Answers (2)

Jackson Burns
Jackson Burns on 7 Sep 2019
The function pol2cart might be what you are looking for.
  4 Comments
Stewart Tan
Stewart Tan on 7 Sep 2019
Edited: Stewart Tan on 7 Sep 2019
@Walter Roberson, spot on!! the image function is multiplied by a rotation matrix. I've been trying to figure it out for weeks now.
Walter Roberson
Walter Roberson on 7 Sep 2019
You will probably find that is a function that produces and coordinate pairs, and that the rotation matrix operates on those to produce and coordinate pairs
Rotation matrices can also be created in terms of polar coordinates
[r(:), theta(:), zeros(numel(r),1)] * [1 0 0; 0 1 dtheta; 0 0 1]
which would increate theta -> theta+dtheta ... though for that simple case it would typically be easier to just do theta = theta + dtheta

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Walter Roberson
Walter Roberson on 7 Sep 2019
If what you have is a formula in terms of x and y, and you need to convert it to polar, and you have the symbolic toolbox, then use
syms r theta
polar_formula = simplify( subs(YourFormula, {x, y}, {r*cos(theta), r*sin(theta)}) )

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