Beyond Intro R

The goal of this workshop is to build upon “introductory content” that is found in other workshops such as Data Carpentry - Data Analysis and Visualisation for Ecologists.

The workshop itself is a bit piecemeal and covers a range of topics and is mostly designed as a source of quick reference for the instructor during the session

The key themes of the workshop are to:

• Cover more about plot customisation using ggplot2
• Look at some of the useful helper functions for data wrangling that exist (mostly in the tidyverse)
• Introduce building and applying custom functions
• And some setup/configuration settings that can be useful

The main reference material is the package documentation itself

R Syntax Refresher

Maths

Mathematical operations:

• + and - for addition and subtraction
• *, /, and %% for multiplication, division, and remainder division
• ^ for exponentiation
• ( and ) for bracketing
• Precedence of operators follows BEDMAS

1 + 6

[1] 7

5 - 3

[1] 2

2 * 9

[1] 18

8 / 4

[1] 2

9 %% 2

[1] 1

2 ^ 3

[1] 8

Assignment

a <- 7

a

[1] 7

Vectors

• must be all of the same type
  • numeric
  • character
  • boolean

b <-c(2, 5, 6)

Indexing (starts from 1)

# 3rd item
b[3]

[1] 6

# Exclude the 2nd item
b[-2]

[1] 2 6

Subsetting with by comparison

# items in b larger than 3
b[ b > 3]

[1] 5 6

# items in b that are equal to 6
b[ b == 6]

[1] 6