基于学习总结和网上收集!汇总供以后查看学习!
+,-,*,/,^,%%。(加,减,乘,除,乘方,求余。)
>,<,>=,<=,==,!=。 (大于,小于,大于等于,小于等于,等于,不等于。)
&,|,!。(与,或,非。)
> getwd()
setwd("")
help(com)
?com
??con
example(com)
args()
library()
library(AER)
require(AER)
library(help = ggplot2)
detach(package:ggplot2)
search()
data()
data(package = .packages(all.available = TRUE))
try(data(package = "ggplot2") )
help(iris)
attach(Affairs)
detach(Affairs)
objects()
ls()
(NULL,numeric,character,logical,complex,list,function)。
mode(x)
class(x)
as.matrix(x)
as.numeric(x)
str(x)
rm(x)
rm(list=ls(all=TRUE))
rm(list=ls())
x = c(1,2,4)
x = c("a","b","cd")
x = paste("a","b","cd")
x[a:b]
x[-i]
length(x)
x = seq(a, b, length = n)
x = seq(a, b, c)
x = seq(a)
x = a:b
x = rep(v, n)
x = rep(v, each = n)
x = round(v)
order(x)
rank(x)
sort(x)
tapply(x,f,g)
split(x,f)
diff(x)
cumsum(x)
M = matrix(0,c(m,n))
> M = rbind(X,Y)
> M = cbind(X,Y)
> colnames(M)
> rownames(M)
> nrow(M)
> ncol(M)
> diag(M)
> M = diag(x)
> dim(M)
> M[i,]
> M[i,,drop = FALSE]
> M = M[-i,]
> M[,j]
> M[i,j]
> t(M)
> X%*%Y
> x%o%y
> X*Y
> eigen(M)$val
> eigen(M)$vec
> solve(M)
> solve(A,b)
> apply(M, dimcode, f, fargs)
> L = list(a = , b = , c = ,...)
> L$a
> L[[a]]
> L$a = NULL
> names(L)
> unname(L)
> lapply(...)
> sapply(...)
> Data = data.frame(...)
> fix(Data)
> head(Data)
> attribute(Data)
> names(Data)
> row.names(Data)
> Data$name1
> Data[i]
> merge(D1,D2)
> is.data.frame(x)
> all(x>a)
> any(x>a)
> x>y
> x[x>a]
> subset(x, x>a)
> which(x, x>a)
x = ifelse(b, u, v)