But returns a logical vector pmatchxtable partial

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Unformatted text preview: vector; can also assign, as substr(x, start, stop) <- value strsplit(x,split) split x according to the substring split grep(pattern,x) searches for matches to pattern within x; see ?regex gsub(pattern,replacement,x) replacement of matches determined by regular expression matching sub() is the same but only replaces the first occurrence. tolower(x) convert to lowercase toupper(x) convert to uppercase match(x,table) a vector of the positions of first matches for the elements of x among table x %in% table id. but returns a logical vector pmatch(x,table) partial matches for the elements of x among table nchar(x) number of characters Dates and Times The class Date has dates without times. POSIXct has dates and times, including time zones. Comparisons (e.g. >), seq(), and difftime() are useful. Date also allows + and −. ?DateTimeClasses gives more information. See also package chron. as.Date(s) and as.POSIXct(s) convert to the respective class; format(dt) converts to a string representation. The default string format is “2001-02-21”. These accept a second argument to specify a format for conversion. Some common formats are: %a, %A Abbreviated and full weekday name. %b, %B Abbreviated and full month name. %d Day of the month (01–31). %H Hours (00–23). %I Hours (01–12). %j Day of year (001–366). %m Month (01–12). %M Minute (00–59). %p AM/PM indicator. %S Second as decimal number (00–61). %U Week (00–53); the first Sunday as day 1 of week 1. %w Weekday (0–6, Sunday is 0). %W Week (00–53); the first Monday as day 1 of week 1. %y Year without century (00–99). Don’t use. %Y Year with century. %z (output only.) Offset from Greenwich; -0800 is 8 hours west of. %Z (output only.) Time zone as a character string (empty if not available). Where leading zeros are shown they will be used on output but are optional on input. See ?strftime. Plotting plot(x) plot of the values of x (on the y-axis) ordered on the x-axis plot(x, y) bivariate plot of x (on the x-axis) and y (on the y-axis) hist(x) histogram of the frequencies of x barplot(x) histogram of the values of x; use horiz=FALSE for horizontal bars dotchart(x) if x is a data frame, plots a Cleveland dot plot (stacked plots line-by-line and column-by-column) pie(x) circular pie-chart boxplot(x) “box-and-whiskers” plot sunflowerplot(x, y) id. than plot() but the points with similar coordinates are drawn as flowers which petal number represents the number of points stripplot(x) plot of the values of x on a line (an alternative to boxplot() for small sample sizes) coplot(x˜y | z) bivariate plot of x and y for each value or interval of values of z interaction.plot (f1, f2, y) if f1 and f2 are factors, plots the means of y (on the y-axis) with respect to the values of f1 (on the x-axis) and of f2 (different curves); the option fun allows to choose the summary statistic of y (by default fun=mean) matplot(x,y) bivariate plot of the first column of x vs. the first one of y, the second one...
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This document was uploaded on 04/10/2014.

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