## January 25, Section 1 ##

## Some functions in R:

c(1,7:9)  # c() concatenates everything in the parentheses into a vector
vec = c(1,7:9)
vec
str(vec) # str() gives details of what's in parens.  data type, size, elements
summary(vec) # gives summary statistics of vector

data(iris)  # dataset iris is loaded (this dataset comes with R)
iris
edit(iris)  # manually edit the data
names(iris) # list column names of data set
summary(iris) # a more interesting summary of dataset

# download APPENC01.txt from website

first <- read.table("c:/413/APPENC01.txt", header=F) # read in rectangular dataset
names(first) #names are V1, V2, etc
first<-edit(first) # change column names manually
names(first) # see that it worked

first$Something # Shows the column named "Something"
first$V3

summary(first$Something)
par(mfrow=c(1,3))  # Let two figures be shown in the same row inside one window.
# make some histograms
hist(first$Something,xlab="Length of Stay",main="SENIC Project") # R chooses bins
hist(first$Something, breaks=seq(4,20,by=4),xlim=c(0,25),ylim=c(0,90),xlab="Length of Stay",main="SENIC Project")
hist(first$Something, breaks=6.5:20.5,xlim=c(0,25),ylim=c(0,40),xlab="Length of Stay", main="SENIC Project")
# look at help(hist) for more options
# Note: We can save or copy this figure (to go into homework reports).

attach(first) # So we don't have to write first$Something all of the time.
Something  # Now, "Something" is its own thing.