Question

I found a code on the web that must (will) produce a graphics representing some data from the U.S. Department of Labor: Bureau of Labor Statistics.:

library(ggplot2)
df <- as.data.frame(read.csv("unemp.csv", colClasses = c("Date", "numeric")))
p <- ggplot(df,aes(x=date,y=ratio))
p + geom_point() + geom_smooth() + xlab("Year") + 
ylab("Civilian Employment Population Ratio (%)") + 
labs(title="Bureau of Labor Statistics Series EMRATIO 
            (seasonally adjusted) to 2012-10-01")

but it do not working and produces this error:

Don't know how to automatically pick scale for object of type function. Defaulting to continuous
Error in eval(expr, envir, enclos) : object 'ratio' not found

What is missing in this code?

‘unemp.csv’ contain data from here and resulting graphics must looking like this.

Answer 1

The error appeared because there weren’t any variables named “date” and “ratio”. This works fine:

 library(ggplot2)
df <- as.data.frame(read.table("unemp.txt", header = TRUE, colClasses = c("Date", "numeric")))
names(df) <- c("date", "ratio")
p <- ggplot(df,aes(x=date,y=ratio))
p + geom_point() + geom_smooth() + xlab("Year") + 
  ylab("Civilian Employment Population Ratio (%)") +
  labs(title="Bureau of Labor Statistics Series EMRATIO (seasonally adjusted) to 2012-10-01")