I have following R data.frame:
group match unmatch unmatch_active match_active
1 A 10 4 0 0
2 B 116 20 0 3
3 c 160 27 1 4
4 D 79 17 0 3
5 E 309 84 4 14
6 F 643 244 10 23
...
My goal is to plot a group by bar plot (http://www.cookbook-r.com/Graphs/Bar_and_line_graphs_(ggplot2)/ section-Graphs with more variables) as shown in the link.
I realize that before getting to that I need to get the data in to following format
group variable value
1 A match 10
2 B match 116
3 C match 160
4 D match 79
5 E match 309
6 F match 643
7 A unmatch 4
8 B unmatch 20
...
I used the melt function:
groups.df.melt <- melt(groups.df[,c('group','match','unmatch', 'unmatch_active', 'match_active')],id.vars = 1)
I don't think I am doing the melt correctly because after I execute above groups.df.melt has 1000+ lines which doesn't make sense to me.
I looked at how Draw histograms per row over multiple columns in R and tried to follow the same yet I don't get the graph I want.
In addition I get following error: When I try to do the plotting:
ggplot(groups.df.melt, aes(x='group', y=value)) + geom_bar(aes(fill = variable), position="dodge") + scale_y_log10()
Mapping a variable to y and also using stat="bin".
With stat="bin", it will attempt to set the y value to the count of cases in each group.
This can result in unexpected behavior and will not be allowed in a future version of ggplot2.
If you want y to represent counts of cases, use stat="bin" and don't map a variable to y.
If you want y to represent values in the data, use stat="identity".
See ?geom_bar for examples. (Deprecated; last used in version 0.9.2)
Error in pmin(y, 0) : object 'y' not found
Try:
mm <- melt(ddf, id='group')
ggplot(data = mm, aes(x = group, y = value, fill = variable)) +
geom_bar(stat = 'identity', position = 'dodge')
or
ggplot(data = mm, aes(x = group, y = value, fill = variable)) +
# `geom_col()` uses `stat_identity()`: it leaves the data as is.
geom_col(position = 'dodge')