Rotating 3D data

I made X, Y coordinates and a triangle with zeros and ones on this plane.

I want to rotate this triangle 45 degrees. I tried rotz(), but I don't have idea to do this.

Thanks in advance.

clc; clear all; close all;

x = linspace(-10,10,49);
y = linspace(-10,10,44);
[X,Y] = meshgrid(x,-y);
Z = zeros(44,49);
Z = importdata('triangle_rotate.txt');
imagesc(Z)

Answer 1

[Chunru]

clc; clear all; close all;
x = linspace(-10,10,49);
y = linspace(-10,10,44);
[X,Y] = meshgrid(x,-y);
Z = zeros(44,49);
Z = importdata('triangle_rotate.txt');
subplot(121); imagesc(Z); axis equal
Z1 = imrotate(Z, 45);
subplot(122); imagesc(Z1); axis equal

[태신 김]

Thank you for your simple answer.

However, the matrix size or image size is changed according to the rotation angle.

Are there other methods to rotate it without changing size of matrix?

Thanks.

[Chunru]

You can either crop the image or resize the image (which may change the object size).

[태신 김]

I mean I want to rotate the data without change of dimension and size.

[Chunru]

If you use a rectangle matrix (with one side along x-axis and another along y-axis) to represent image, you will get different size of rectangle (along x and y) to enclose the rotated image. So you cannot get the same dimension (except for some special case, eg. rotate by 180 deg) in this sense.

[Matt J]

You can use the crop option to keep the array the matrix the same size, but there is no guarantee the rotated object will fit inside the original borders:

Z = importdata('triangle_rotate.txt');
Z=imrotate(Z,45,'bicubic', 'crop');

[태신 김]

Thank you for your helpful answers.