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expression1. expressionIf you want to write math symbol or expression in R plot, you can use function expression, which give you a formed latex style. And the expression can be included in plot ti

This is a short code for studying admm for lasso.#--------------------------- functions to be used ----------------------## the main function f = g + hf <- function(x, A, b, lambda){ 1/2*norm(

For R, use Ctrl+Shift+C to add and delete multi-line comments.For MATLAB, us Ctrl+R to add multi-line comments and Ctrl+T to delete multi-line comments.

Week 1This course is following thatRaw data →\rightarrow Processing script →\rightarrow Tidy data →\rightarrow Data analysis →\rightarrow Data communicationRaw Data VS Processed Data:Raw DataThe ori

Quiz 1Question 1QUestion 2Question 3Question 4Question 5For more detail, you can download the html file here.Quiz 1Question 1The American Community Survey distributes downloadable data about Unit

一 Installing RMySQL package under Window二 Playing with RMySQL一. Installing RMySQL package under WindowThis section is from the instruction given in the following website http://www.ahschulz.de/2013/

[TOC] For more detail, see the html file here[http://download.youkuaiyun.com/detail/comeyan/9460707].Week 2Reading data from MySQLWhat is MySQL? SQL is short for Structured Query Language and MySQL is the w

Question 1Question 2Question 3Question 4Question 5For more detail, see the html file here.Question 1Register an application with the Github API here github application. Access the API to get info

R command:nohup R CMD BATCH (your file) &MATLAB command:nohup matlab <file.m> file.out&

Tell you how to write Chinese report using R markdown.

Convert long form data to wide or wide to long.

1. XGBoost介绍XGBoost模型即是一些“串联”树结构的组合，最终预测结果由多棵树共同决定。 模型公式：y=f(z)=∑Kk=1fk(z)y=f(z)=∑k=1Kfk(z)y=f(z)=\sum_{k=1}^K f_k(z) 模型预测：y^i=∑Kk=1f^k(xi)y^i=∑k=1Kf^k(xi)\hat y_i = \sum_{k=1}^K \hat f_k(x_i...

This is a short code for studying proximal gradient descent algorithm.#--------------------------- functions to be used ----------------------## the main function f = g + hf <- function(x, A, b, lambd

Project summaryReview criteriaLoading the dataMaking PlotsCodeProject summaryThis assignment uses data from the UC Irvine Machine Learning Repository, a popular repository for machine learning dat

Benchmark package consists of only one function benchmark, which is a simple wrapper of system.time to evaluate expression of R code.Usage: benchmark(...,columns = c("test", "replications", "elapsed",

Alternative solutions for list of matrix or dataframeAlternative solutions for list of list1. Alternative solutions for list of matrix or data.frameIf I have a list of matrix or data.frame, we can use

foreach packageExamples1. foreach packageThe foreach package provides a new looping construct for executing R code repeatedly. The main reason for using the foreach package is that it supports paralle

Week 4Editing text variablesRegular expressionsWorking with datesMore details could be found in the html file here Week 4Editing text variablesImportant points about text in data setNames of variab

Week 3Subsetting and SortingSummarizing dataCreating new variablesReshaping dataManaging data frame with dplyr package IntroductionManaging data frames with dplyr package Basic toolsMerging da

Basic functionsComplex functions1. Basic functionsThe basic functions of R to deal with regular expression is nchar, tolower, toupper, chartr, paste.nchar gives the number of characters of each eleme

A friend of mine asked me the other day how she could use the function optim in R to fit data. Of course there are built in functions for fitting data in R and I wrote about this earlier. However, she

Question 1Question 2Question 3Question 4Question 5More details can be found in the html file here.Question 1The American Community Survey distributes downloadable data about United States communit

Question 1Question 2Question 3Question 4Question 5More details can be found in the html file here.Question 1The American Community Survey distributes downloadable data about United States communit

Project introductionProject codeMore details can be found here.Project introductionThe purpose of this project is to demonstrate your ability to collect, work with, and clean a data set.Review criter

Manipulating Data with dplyr PackageGrouping and Chaining with dplyr packageTidying Data with tidyr packageType one column headers are values not variable namesType two multiple variables are stored

Principles of analysis graphicsExploratory GraphicsPlottingBase Plotting SystemGraphics DeviesPrinciples of analysis graphicsPrinciple 1: Show corparisons Evidence for a pyhothesis is always rel

Figure 10.2Firstly define the function to generate simulated data.# function for generating data for figure 10.2gen_eq_10_2_data &amp;amp;amp;amp;lt;- function(N = 2000, p = 10){ X &amp;amp;amp;amp;lt;- matrix( rnorm(N*p), ...