# R Quick Reference I

The article is about R Quick Reference related to Data representation in R Language, Data Types in R, Checking/Testing of special values in R, Changing the basic data types, use of Mathem operations, rounding of the numbers and outputs, and mathematical functions.

### R Quick Reference

R language: A Quick Reference is about learning R Programming with a short description of the widely used commands. It will help the learner and intermediate user of the R Programming Language to get help with different functions quickly. This R Quick Reference is classified into different groups. Let us start with R Language: A Quick Reference – I.

### Basic Data Representation in R

In R, data may be represented as logical values, in scientific notation, as a complex, or as a float number. The are certain values such as NA, NULL, NaN, and Inf values.

### Checking/ Testing the Basic Data Types in R

The type of data can be checked using some functions such as is.logical(), is.numeric(), is.list(), is.character(), is.vector() or is.complex() function.

### Checking/ Testing the Special Values

The type of special values can be checked using is.na(), is.nan(), is.finite(), is.ordered(), and is.factor() etc., functions

### Changing Basic Data Types in R

The Data Types in R can be changed by using functions such as, as.logical(), as.numeric(), as.list(), or as.numeric() etc., functions.

### Basic Mathematical Operations

R can be used as a calculator. Mathematical operations such as addition, subtraction, multiplication, and division can also be performed.

### Rounding off the Numbers

The numbers or values of a variable can be rounded as desired.

### Common Mathematical Functions

The commonly used mathematical functions in the R language are abs(), sqrt(), exp(), log(), and different bases of log functions.

### Trigonometric and Hyperbolic Functions

Following is the list of different trigonometric and Hyperbolic functions

### Special Mathematical Functions

The following is the list of special mathematical functions.