R in Action reading notes (1)--fifth: Advanced data management

5.2.1 Mathematical Functions
Function	Describe
ABS (x)	Absolute
sqrt (x)	Square root
Ceiling (x)	Smallest integer not less than X
Floor (x)	Largest integer less than x
Trunc (x)	The integer portion of x that is intercepted in the direction of 0
Round (X,digits=n)	Rounds x to a decimal of a specified bit
Signif (x, Digits=n)	Rounds x to the specified number of significant digits
cos (x), sin (x), tan (x)	Cosine, sine, and tangent
ACOs (x), ASIN (x), Atan (x)	Inverse cosine, anyway chord and anyway tangent
Cosh (x), Sinh (x), Tanh (x)	Hyperbolic cosine and hyperbolic sine hyperbolic tangent
Acosh (x), Asinh (x), Atanh (x)	Inverse hyperbolic cosine, inverse hyperbolic sine, and inverse hyperbolic tangent
Log (X,base=n)	N-Base logarithm of X
Log (x)	Natural logarithm
LOG10 (x)	Common logarithm
EXP (x)	exponential function

5.2.2 Statistical functions
Mean (x)	Average
Median (x)	Number of Median
SD (x)	Standard deviation
var (x)	Variance
Mad (x)	Absolute median difference
Quantile (X,probs)	Finding the number of bits
Range (x)	Ask for a domain
SUM (x)	Sum
diff (X, lag=n)	hysteresis differential, lag used to specify several lags
Minx	To find the minimum value
Max (x)	To find the maximum value
Scale (X,center=true,scale=true)	Centering or standardizing on columns for data Objects X
5.2.3 probability function
Beta distribution	Beta
Two item distributions	Binom
Cauchy distribution	Cauchy
(non-center) Chi-square distribution	Chisq
Exponential distribution	Exp
F Distribution	F
Gamma When in cloth	Gamma
Geometric distribution	Geom
Super Geometric distribution	Hyper
Logarithmic normal distribution	Lnorm
Logistic distribution	Logis
Multi-item Distribution	Multinom
Negative two-item distribution	Nbinom
Normal	Norm
Poisson distribution	POIs
Wilcoxon symbol Rank Distribution	Signrank
T distribution	T
Evenly distributed	Unif
Weibull distribution	Weibull
Wilcoxon Rank and distribution	Wilcox
5.2.4 Character processing function
NCHAR (x)	Calculate the number of characters in X
SUBSTR (x, Start, stop)	Extracts or replaces substrings in a character vector
grep (pattern, x, Ignore.case=false,fixed=false)	Search for a pattern in X. If fixed=false, the pattern is a regular expression. If fixed=true, the pattern is a text word Fuschen. The return value is the matching subscript
Sub (pattern, replacement, X,ignore.case=false, Fixed=false)	Search for pattern in X and replace it with text replacement. If fixed=false, the pattern is a regular expression if fixed=true, then the pattern is a text string
Strsplit (x, Split, Fixed=false)	Splits the Yenso in the character vector x at split. If fixed=false, the pattern is a regular expression. If fixed=true, the pattern is a text word Fuschen
Pas seven E (..., sep= "")	Connection Word Fuschen, the separator is Sep
ToUpper (x)	Uppercase Conversion
ToLower (x)	lowercase conversions
5.2.5 Other Utility functions
Length (x)	Length of Object X
Seq (from, to, by)	Generate a sequence
Rep (x, N)	Repeat x N times
Cut (x, N)	The continuous type variable is cut to a factor with n levels
Pretty (x, N)	Create beautiful split points. By selecting the N+1 value of equal spacing, a continuous variable is cut to n intervals.
Cat (..., file = "MyFile", append =false)	Connection '}, the object that the well outputs to the screen or file '}, (if one is declared)

R in Action reading notes (1)--fifth: Advanced data management