R4DS-2e Ch. 15

str_replace_all()

{stringr}

replace all matched patterns in a string

library()

{base}

load R packages

set_names()

{magrittr}

set names of object

str_to_lower()

{stringr}

change text to lower case

year()

{lubridate}

return or set year component of a date-time

count()

{dplyr}

count unique values of variables

ggplot()

{ggplot2}

create a plotting area

colors()

{grDevices}

returns vector of color names in R

str_match()

{stringr}

extract first matched group from a string

mutate()

{dplyr}

create or modify data columns

filter()

{dplyr}

keep rows based on values of columns

str_extract()

{stringr}

extract first matching patterns in a string

group_by()

{dplyr}

group data by levels of column

str_view()

{stringr}

view first regular expression match

head()

{utils}

return first rows of matrix, data frame, etc.

str()

{utils}

return object structure

n()

{dplyr}

return current group size

c()

{base}

create vector of numbers, characters, etc.

aes()

{ggplot2}

create aesthetic mappings between data and plot

str_count()

{stringr}

count number of matches in a string

str_remove_all()

{stringr}

remove all instances of a pattern in a string

str_flatten()

{stringr}

flatten a string

tribble()

{tibble}

create row-wise tibble

str_replace()

{stringr}

replace first matched pattern in a string

summarize()

{dplyr}

summarize data usually by grouping variable

geom_line()

{ggplot2}

add layer of data lines to plot

coll()

{stringr}

compare strings respecting standard collation rules

str_detect()

{stringr}

detect presence of pattern in string

as_tibble()

{tibble}

coerce object into tibble

mean()

{base}

calculate mean of elements of vector

str_c()

{stringr}

combines two or more strings

fixed()

{stringr}

compare literal bytes in a string

regex()

{base}

use regular expressions

apropos()

{utils}

return vector of object names matching pattern

The end!