Draw a square, and then rotate it with rcos/rsin?

Hi! I'm trying to draw a square, and then use various inputs to try and rotate it/move it around. But I'm not sure how I'm supposed to solve this.

It's supposed to be 2x2 matrix using sin and cos to rotate it.

I'm fairly new to Matlab.

Any ideas or hints on how to tackle this?

Thank you in advance.

Answer 1

[Image Analyst]

Sounds like homework so I won't just do it for you. I'm sure you already know the rotation array from Wikipedia or wherever:

rotationArray = [cosd(theta) sind(theta); -sind(theta) cosd(theta)];

But I've attached a demo that I already have that rotates an ellipse by varying angles. You should be able to take that example and apply it to a list of square coordinates rather than ellipse coordinates.

[Image Analyst]

Alexander's "Answer" moved here:

Thank you. Yes, it's homework, but since none of my mates knew how to tackle it either, I figured we needed some aid. I'll try and analyze the code and see if I understand all the steps so I'll learn.

Appreciate the help.

Answer 2

[chen xi li]

d = sin2(π/6) + cos2(π/6) how to input it

[Image Analyst]

Assuming the 2 means "squared", like this:

d = sin(pi/6) ^ 2 + cos(pi/6) ^ 2

you will, of course, get exactly 1.

Answer 3

[chen xi li]

bmi how to solve it

[Image Analyst]

He probably simply adapted my rotate_ellipse. It's trivial. Did you actually even try it?