Tag：matrix

Time：2021415
Let’s first explain why we need to convert an array to an image class. The image I process is fits (flexible image transport system) file, which is a gray image file, that is, a single channel image. The feature of fits image is that the gray value is from 0 to 65535. This kind of […]

Time：2021412
brief introduction The scene will be based on the machine learning Pai platform to guide you how to use ALS algorithm to achieve user music score prediction. background information ALS algorithm is a modelbased recommendation algorithm. The basic idea is to decompose the sparse matrix and evaluate the value of missing items to get a […]

Time：2021412
Let’s review What did we talk about in the last part? Steam locomotive sl Turn into a small locomotivel Flying locomotivef Let’s drive again sl Last time I wanted to see the matrix?! Matrix matrix `apt search matrix apt show cmatrix sudo apt install cmatrix ` Found a package called CMatrix It takes 2m to […]

Time：2021411
summary First of all, you need to understand why we need to use distributed algorithms to calculate our combinatorial optimization problem (a QAP problem). In actual production, even if we build the standard two level programming model based on the traditional MV theory, the two term coefficient is positive definite matrix, then the constraint condition […]

Time：202148
Link to the original text:http://tecdat.cn/?p=20360 This paper will explain the R language in financial mathematics to optimize the portfolio, the implementation and use of factor model. Macroeconomic factor model with single market factor We’ll start with a simple example of a single known factor, the market index. The model is The explicit factor ft […]

Time：2021325
I feel that the drawing in the second chapter of the book is a little bit messy. It doesn’t seem to fit in. I plan to split it into three parts Coordinate system and deformation Path drawing Rendering Coordinate systemDeformation is the basis of canvas drawing, and deformation is closely related to coordinate system.Path drawingIs […]

Time：2021324
C + + read in “n, x, y, Z” format text file to eigen3 matrix, and the same format output method Many data formats are similar to this: 1,2085738.7757,5503702.8697,2892977.6829 2,2071267.5135,5520926.7235,2883341.8135 3,2079412.5535,5512450.8800,2879771.2119 4,2093693.1744,5511218.2651,2869861.8947 5,2113681.5062,5491864.0382,2896934.4852 6,2100573.2849,5496675.0138,2894377.6030 The data is sorted by n (point number), x, y, Z (threedimensional coordinates). This paper provides a method for C + […]

Time：2021322
Link to the original text:http://tecdat.cn/?p=21317 This paper provides an example of running a distributed lag nonlinear model, and describes the nonlinear and lag effects between the predicted variables and the results, which is defined as the exposure lag response correlation. data The data set contains daily mortality (CVD, respiratory tract), weather (temperature, relative humidity) and […]

Time：2021317
By Rashida nasrin suckyCompile VKSource: towards Data Science Python is open source. Numpy is essential for data scientists who use python. Other basic libraries, such as pandas and SciPy, are based on numpy. So I decided to make a memo. I’ve included all the numpy functions I’ve used so far. I believe these functions will […]

Time：2021316
catalog:Source code analysis of Android jar / Library Zxing： effect: Generation and identification, QR code, barcode. Chestnut: Generate QR code and assign value to ImageView QRCodeWriter qrCodeWriter = new QRCodeWriter(); Map hints = new HashMap<>(); hints.put ( EncodeHintType.CHARACTER_ Set, “UTF8”); // remember to customize the length and width BitMatrix encode = null; try { encode […]

Time：2021315
Chap 04 recommendation engine based on spark Amazon, Netflix, youtube, twitter, LinkedIn and Facebook recommendation are among the core functions behind these websites The idea behind the recommendation engine is to predict the items people might like and assist the process by exploring the connections between the items.Different from search engines, the content that recommendation […]

Time：2021311
The experiment code has been uploadedMore bread, please click to buyOr, attention [all code farmer] official account, reply to [nearest neighbor], time limited free access! Experimental overview In this experiment, opencv, Python and other tools are used to recognize and detect handwritten numbers by using appropriate algorithms. Training set and test set can be provided […]