I have almost complete the following graph, but there is one problem with it.
The legend in the graph is drawn twice.
Here is the data:
structure(list(Period = c("January 1997 - August 2003", "September 2003 - Jun 2005",
"Jul 2005 - Dec 2009", "January 1997 - August 2003", "September 2003 - Jun 2005",
"Jul 2005 - Dec 2009"), Time.Period = structure(c(1L, 3L, 2L,
1L, 3L, 2L), .Label = c("Jan 1997 - Aug 2003", "Jul 2005 - Dec 2009",
"Sep 2003 - Jun 2005"), class = "factor"), Variable = structure(c(2L,
2L, 2L, 1L, 1L, 1L), .Label = c("Significant", "Zscore"), class = "factor"),
Score = c(8.798129, 4.267268, 7.280275, 1.64, 1.64, 1.64)), .Names = c("Period",
"Time.Period", "Variable", "Score"), class = "data.frame", row.names = c(NA,
-6L))
ggplot(glomor, aes(x=Time.Period, y=Score, group=Variable, shape=Variable, color=Variable)) +
geom_point() +
guides(fill=FALSE) +
scale_x_discrete(limits=c("Jan 1997 - Aug 2003","Sep 2003 - Jun 2005","Jul 2005 - Dec 2009"), expand=c(.08,0)) +
geom_line(aes(linetype=Variable), size=1.5) +
geom_point(size=4.2) +
scale_linetype_manual(values=c(1,3)) +
scale_color_manual(values=c("black", "grey40"), name="", labels=c("Signficant Z-Score", "Moran's I Z-Score")) +
scale_fill_discrete(name="", label=c("Signficant Z-Score", "Moran's I Z-Score")) +
theme_classic()+
ylim(0,10) +
xlab("Time Periods") +
ylab("Moran's I Z-Score") +
theme(axis.title.x=element_text(size=14)) +
theme(axis.title.y=element_text(size=14)) +
theme(legend.position=c(.75, .85)) +
theme(legend.background = element_rect(fill="white")) +
theme(legend.key = element_blank())
Does anyone know, why the ggplot2 produces two legends?
You have three aesthetics that are mapped to Variable
: shape, colour, and linetype. Legends are collapsed together when they have the same title and labels. You have set the title to blank for colour and given it custom labels ("Significant Z-Score" and "Moran's I Z-Score"). You need to do that for linetype and shape as well to get them to collapse all together.
Change
scale_linetype_manual(values=c(1,3)) +
to
scale_linetype_manual(values=c(1,3), name="", labels=c("Signficant Z-Score", "Moran's I Z-Score")) +
and add
scale_shape_discrete(name="", label=c("Signficant Z-Score", "Moran's I Z-Score")) +
(You can also get rid of the scale_fill_discrete
because you don't actually use the fill aesthetic anywhere.)
This gives