• CorelDRAW tutorial: how to use pen tool — win10 Professional Edition

Time：2021-1-26

How to use CorelDRAW pen tool? CorelDRAW is a graphics and image software. Its extraordinary design ability is widely used in trademark design, logo making, model drawing, illustration drawing, typesetting and color separation output and many other fields. Its pen tool mainly draws lines one by one (curve or straight line) by accurately placing nodes […]

• [in depth] supervised learning: starting from a good label

Time：2021-1-17

In our algorithm work, we will train a variety of models. There are many reasons for the poor practical application effect of our models. Some common reasons are unreasonable model structure, unreasonable loss function and unreasonable setting of super parameters. But in addition to these reasons, I think the core reason is the quality of […]

• Auc-roc curve in machine learning

Time：2020-12-24

By aniruddha BhandariCompile | VKSource: analytics vidhya Auc-roc curve You’ve built your machine learning model – so what’s next? You need to evaluate it and verify how good (or bad) it is so that you can decide whether to implement it or not. At this point, the auc-roc curve can be introduced. The name may […]

• Flutter learning notes (37) — animation curves effect

Time：2020-12-20

If you want to reprint, please indicate the source:Flutter learning notes (37) — animation curves effect

• Automatic backlight algorithm – Android 8.1

Time：2020-12-20

In this paper, based on the work of automatic backlight notes, expand the next, record the automatic backlight algorithm.Based on Android 8.1, the code can be referred to http://androidxref.com/8.1.0_ …Android 9 adds a so-called machine learning algorithm to regenerate curves according to the brightness and light perception of users when they adjust them,The slide bar […]

• Add silky water ripples to the view

Time：2020-11-16

Let’s take a look at the final renderings First of all, we can split such a smooth water ripple A regular curve. The curve moves to the right uniformly. The position below the curve is colored. So let’s start with a curve. For the curve that needs to produce such a regular fluctuation, we should […]

• 3. SVM support vector machine

Time：2020-10-24

Idea: find a curve so that the minimum distance between all sample points and this curve is the maximum Distance from point x to line: $$l = \frac{1}{{\left\| w \right\|}}({w^T}x + b)$$ For two categories, Y values are only – 1 and 1, then the same sign indicates that the classification is correct, […]

• Machine learning — LR classification model analysis

Time：2020-10-23

LR analyze There is an interesting question: clearly LR is used for classification, why should we call it expression regression?? In the last chapter, we dredged the mathematical theory, modeling basis and loss function optimization method of LR algorithm, and we can answer this question with a little thinking. In this chapter, we will analyze […]

• Canvas series tutorial 02 – lines and curves

Time：2020-10-9

In the last article, we set up the basic environment, and then drew a rectangle to play with. As for how to draw rectangular wireframes, just look at the manual. It’s not complicated. If the parameters are correct, don’t spell the words wrong This article talks about the common pits and curves that are more […]

• ROC of classification evaluation index

Time：2020-9-29

ROC of classification evaluation index What is ROC curve ROC (receiver operating characteristic curve) is called the receiver operating characteristic curve in Chinese. The abscissa of ROC represents the false positive rateFPRThe ordinate represents positive rateTPR。 Their calculation formula is as follows $$\begin{cases}TPR = \frac{TP}{TP+FN}\\FPR=\frac{FP}{FP+TN}\end{cases}$$ To give a simple example, there are now 10 patients […]

• Drawing a curve animation with canvas

Time：2020-9-27

My GitHub blog address https://github.com/hujiulong/… preface In front-end development, Bessel curve is everywhere: It can be used to draw curves. In SVG and canvas, Bezier curve is used in the original curve drawing It can also be used to describe a slow motion algorithm to set thetransition-timing-functionProperty, Bezier curve can be used to describe the […]

• Canvass advanced order Bessel formula derivation and object’s track motion following complex curve

Time：2020-9-21

Write it first In the previous article, we mentioned the use of Bessel’s formula. Let’s share how to deduce Bessel formula and attach a simple one, that is, the ball follows the curve trajectory. Welcome to follow my blog, which is updated from time to time—— Effect preview Demo address For how to draw continuous […]