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Statistics Cheat Sheet

help about maximum values on your machine

the names of all objects in the search list matching the regular expression 'topic'

show files in the current directory

search the help system

start the HTML version of help

documentation on topic

str() for each variable in the search path

show objects in the search path; specify pat='pat' to search on a pattern

shows S3 methods of a

lists all the methods to handle objects of class a

display the internal structure of an R object

gives a 'summary' of a, usually a statistical summary but it is generic meaning it has different operations for different classes of a

prints the arguments after coercing to character; sep is the character separator between arguments

loads specified data sets

read tables with office applications on windows via clipboard

format an R object for pretty printing

load add-on packages

load the datasets written with save

prints its arguments; generic, meaning it can have different methods for different objects

id. but with defaults set for reading comma-delimited files

id. but with defaults set for reading tab-delimited files

read a table of f ixed width f ormatted data into a 'data.frame'

sep="" is any whitespace by default

saves all objects

saves the specified objects (...) in the XDR platform-independent binary format

output to f, until sink()

includes and executes my.R in this place

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prints x after converting to a data frame

array with data x; specify dimensions like dim=c(3,4,2); elements of x recycle if x is not long enough

combine arguments by columns for matrices, data frames, and others

create a data frame of the named or unnamed arguments; data.frame(v=1:4,ch=c(

encodes a vector x as a factor

generate levels (factors) by specifying the pattern of their levels; k is the number of levels, and n is the number of replications

create a list of the named or unnamed arguments; list(a=c(1,2),b=

matrix; elements of x recycle

combine arguments by rows for matrices, data frames, and others

replicate x times; use each= to repeat “each” element of x each times; rep(c(1,2,3),2) is 1 2 3 1 2 3; rep(c(1,2,3),each=2) is 1 1 2 2 3 3

generates a sequence by= specifies increment

generates a sequence length=specifies desired length

generic function to combine arguments with the default forming a vector; with recursive=TRUE descends through lists combining all elements into one vector