26 lines
934 B
R
26 lines
934 B
R
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# Goal: To read in a simple data file, and look around it's contents.
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# Suppose you have a file "x.data" which looks like this:
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# 1997,3.1,4
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# 1998,7.2,19
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# 1999,1.7,2
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# 2000,1.1,13
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# To read it in --
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A <- read.table("x.data", sep=",",
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col.names=c("year", "my1", "my2"))
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nrow(A) # Count the rows in A
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summary(A$year) # The column "year" in data frame A
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# is accessed as A$year
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A$newcol <- A$my1 + A$my2 # Makes a new column in A
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newvar <- A$my1 - A$my2 # Makes a new R object "newvar"
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A$my1 <- NULL # Removes the column "my1"
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# You might find these useful, to "look around" a dataset --
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str(A)
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summary(A)
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library(Hmisc) # This requires that you've installed the Hmisc package
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contents(A)
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describe(A)
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