- SQL basics
1. Query the number of students enrolled in each course 2. Query the student numbers and names of all students who have taken only 4 courses 3. Query the list of students with the last name 4. Query the list of students with the same name and count the same names. ..

- Detailed decision tree with Excel and python
Select the one with a large gain ratio to implement the division using python code: The result is: ['no' 'yes'' yes' 'yes'' no '' no '' yes' 'ye ...

- Watermelon Book-Linear Model
2. Linear Regression Linear Regression: Try to learn a linear model to predict real-valued output labels as accurately as possible 3. Logarithmic probability regression classification task: find a monotonic differentiable function to classify the true label y of the classification task with ...

- Watermelon Book-Introduction
Machine learning is dedicated to studying how to use computing to improve the performance of the system itself. In computer systems, "experience" usually exists in the form of "data", so the main content studied by machine learning ...

- matplotlib plots box plots, error bar plots, stacked plots, etc.
1. Box chart Box chart is a statistical figure composed of a box body and a pair of box whiskers. The cabinet is composed of the first quartile, the median (second quartile), and the third quartile. Values outside the end of the box whisker ...

- Improve statistical graphics
1. Multiple graphics may appear in the drawing area, and if these graphics are not explained, it is difficult for the observer to identify the main content of these graphics. So we need to add label instructions to these graphics to mark ...

- Draw simple graphs using statistical functions
Use matplotlib to draw some familiar and often confused statistical graphics. Mastering these statistical graphics can have a deep understanding of data visualization. 1.function bar ()-for drawing bars ...

- Chart elements of "matplotlib"
matplotlib library is a data visualization tool for drawing 2D and 3D charts in Python. Its main features are as follows: 1. Use simple drawing statements to achieve complex drawing effects 2. Interactive operation ...

- LeetCode1-5 questions
1. The sum of two numbers gives an integer array nums and a target value target. Please find the two integers whose sum is the target value in the array and return their array index 2. Two numbers ...