R language is a very convenient data analysis language, which has many methods of matrix processing. Here are some common examples of matrix operations.
The generation of matrix
> mat <- matrix(1:16, ncol = 4, nrow = 4, byrow=TRUE, dimnames=list(c(paste("x", 1:4, sep = ".")), c(paste("y", 1:4, sep = "."))))
y.1 y.2 y.3 y.4
Posted on Sat, 15 Feb 2020 06:29:43 -0800 by Brentley_11
The grep function family can search for text in a given object through regular expressions. Grep outputs the vector subscript or value, and grepl returns the logical value of matching or not. regexpr, gregexpr and regexec can find the specific location and string length information of some characters in the string, which can be ...
Posted on Sat, 04 Jan 2020 20:29:31 -0800 by dbillings
Newton Raphson iterative method based on R language (for binary differentiable function)
Newton Raphson method is an iterative method based on the initial value guess of the root. The function used in this method is the original function and the derivative of the original function. If it succeeds, it usu ...
Posted on Sun, 01 Dec 2019 15:29:02 -0800 by samoht
Near the double 11, I found that I was really poor, very poor, very poor
Poverty is a catalyst for progress. So I think about how to play the game of making money in my spare time. After all, even if it is destined to make leeks, it is also necessary to make an intellectual and ideal leek.
The first model to play is the golden cross of average ...
Posted on Thu, 07 Nov 2019 13:30:23 -0800 by lanas
Summary of this article:
R Language Data Structure and Example Operation
Python Language Data Structure and Example Operation
Data Structure and Example Analysis of R Language
Then we begin to learn the five data structures of R language: vector, matrix, array, data box and list.
Posted on Fri, 02 Aug 2019 02:25:42 -0700 by Panthers
It is single nucleotide polymorphism. Human genes are similar, and there are differences at some loci. The nucleotide difference at one locus is called single nucleotide polymorphism. It affects biological characteristics and susceptibility to certain diseases. SNPedia is an encyclopedia of SNP. It uses various published articles or database in ...
Posted on Sat, 13 Apr 2019 09:57:32 -0700 by phpian
The template of common data analysis model of R language is compiled by myself. The original file is in Rmd format. It is copied and pasted directly, and saved and shared as personal learning notes. Part of the reference is Xue Yi's "Statistical Modeling and R Software" and "R Language Practice"
Factor model: X=mu+A*F*+e
Posted on Sun, 07 Apr 2019 11:33:30 -0700 by Delqath
Note: Don't ask me why I wrote so fast. It was written in 16 years.
Advantages of R: Free, friendly interface (without matlab friendliness, MATLAB in my mind is the representative of minimalism in statistical software), small (compressed package is tens of M, compressed package of MATLAB.R2009b is 1.46G), many (really many, friends often upload ...
Posted on Fri, 05 Apr 2019 23:30:30 -0700 by diondev