Question

I have this data frame, this is a daily data. For every day, I have free space for each file system. I like to graph this. I was thinking to put each file system on its own column to create R graphs. How can I go about doing this. Without moving them to their own columns, can I create a chart for each file system for each day?

     Date     fileSystem FreeSpace
2011-12-03     /var          99.785
2011-12-03     /opt          30.494
2011-12-03     /tmp          55.643
2011-12-03     /data         37.846
2011-12-03     /ora          0.578
2011-12-04     /var          99.785
2011-12-04     /opt          30.494
2011-12-04     /tmp          55.643
2011-12-04    /data         37.846
2011-12-04     /ora          0.578

Answer 1

There are many possibilities for this in R… Something like this?
However if you want to plot for each file system and each day, there would be only one bar (don`t if this is much usefull…).

df <- read.table(header = TRUE, text = "Date     fileSystem FreeSpace
                 2011-12-03     /var          99.785
                 2011-12-03     /opt          30.494
                 2011-12-03     /tmp          55.643
                 2011-12-03     /data         37.846
                 2011-12-03     /ora          0.578
                 2011-12-04     /var          99.785
                 2011-12-04     /opt          30.494
                 2011-12-04     /tmp          55.643
                 2011-12-04    /data         37.846
                 2011-12-04     /ora          0.578
                 ")

## using ggplot (dates are faceted)
require(ggplot2)
ggplot(df, aes(x = fileSystem, y = FreeSpace)) +
  geom_bar() +
  facet_wrap(~Date)

Edit:
or as a line chart. Nearly everything is possible in R, but you must think about what kind of plot you want…

df$Date <- strptime(df$Date, format="%Y-%m-%d")
ggplot(df, aes(x = Date, y = FreeSpace)) +
  geom_line() +
  facet_wrap(~fileSystem)

Edit2:
Perhabs this? Here I make a plot for every filesystem with a for-loop. The plots are stored in a list.

# or as a line chart
df$Date <- strptime(df$Date, format="%Y-%m-%d")
plotlist <- vector(mode="list", length(levels(df$fileSystem)))
for(i in levels(df$fileSystem)){
  tempdf <- df[df$fileSystem == i, ]
  plotlist[[i]] <- ggplot(tempdf, aes(x = Date, y = FreeSpace)) +
    geom_line() +
    opts(title = i)
}
plotlist[["/data"]]
plotlist[["/var"]]