Three-dimensional transformation matrix practice – rotation, scaling, mirroring, cross-cutting, translation, and orthogonal projection of three-dimensional point clouds

1. Rotation matrix (right-handed coordinate system) Rotate around the x-axis Rotation matrix: The matrix on the right is the original coordinates of the point cloud, and the matrix on the left is the rotation matrix Visualization: Rotate 90 degrees around the x-axis Code: import vtk import numpy as np import math def pointPolydataCreate(pointCloud): points = […]

Principal Component Analysis (PCA) MATLAB project example “Fitting an Orthogonal Regression Using Principal Components Analysis”

Fitting an Orthogonal Regression Using Principal Components Analysis Orthogonal regression fitting via principal component analysis 1. Background analysis This example shows how to use Principal Components Analysis (PCA) to fit a linear regression. PCA minimizes the perpendicular distances from the data to the fitted model. This is the linear case of what is known as […]

5. Design (black box) test cases (2) Orthogonal Table Method & Scenario Design Method & Error Guessing Method

Directory 1. Orthogonal table 1.1 Concept 1.2 Orthogonal table method design test case 1.2.1 Steps 1.2.2 Examples 2. Scenario Design Method 2.1 Concept 2.2 Scenario design method to design test cases 2.2.1 Steps 2.2.2 Examples 3. Wrong Guessing 3.1 Concept 3.2 Example 4. Case 4.1 Simulate Weak Network 4.2 cd linux command test 4.3 Testing […]

Android audio and video development – OpenGL ES orthogonal projection implementation method

The example in this article shares the specific code of the OpenGL ES orthogonal projection display for your reference. The specific content is as follows Draw a square The hexagon drawn at the beginning seems to be very easy, and there is no problem. Next, we might as well forget the previous code for drawing […]

Matlab Implementation Example of Empirical Orthogonal Decomposition EOF

In geosciences, PCA and EOF are usually used for signal extraction. Separating the spatiotemporal variation characteristics of geographic elements from complex spatiotemporal data is a prerequisite for geoscience signal analysis. In essence, there is no difference between PCA and EOF, except that: EOF is a spatial feature vector, also known as a spatial mode, which […]