问题
Apart from this post, here I am asking new questions how to make adjustment in legends built by ggraph.
Here are scripts to produce current plot:
## Packages
library(igraph)
library(tidygraph)
library(ggraph)
library(ggplot2)
library(tidyverse)
## Edge and node
edge <- data.frame(from=c(0,0,0,0,1,2,3),
to=c(0,1,2,3,0,0,0),
weight=c(1,3,1,1,3,1,1))
node <- data.frame(id=c(0,1,2,3),
p=c(9,1,0,0),
w=c(0,2,0,0),
s=c(0,1,1,1),
size=c(9,3,1,1),
gr=c(0,1,1,2))
## Load data frames as tbl_graph class
edge <- edge %>% mutate(from=from+1,to=to+1)
net <- tbl_graph(nodes=node,edges=edge,directed=TRUE)
## Set arrows
ar <- arrow(angle=30,length=unit(5,"mm"),ends="last",type="closed")
## Plot
ggraph(net,layout="graphopt") +
## Edges
geom_edge_link(aes(start_cap=circle(log(node1.size)+2,unit="native"),
end_cap=circle(log(node2.size)+2,unit="native"),
width=weight,label=weight),
position="identity",angle_calc="along",force_flip=TRUE,
label_dodge=unit(4.0,"mm"),label_push=unit(-0.4,"mm")) +
## Width scale
scale_edge_width(range=c(0.4,4),breaks=c(1:10),name="Movements\nbetween zones") +
## Add arrows separately
geom_edge_link(arrow=ar,aes(start_cap=circle(log(node1.size)+1,unit="native"),
end_cap=circle(log(node2.size)+1,unit="native"))) +
## Nodes
## Plot location id
geom_node_label(aes(label=id,hjust=log(size+6),vjust=log(size+6)),repel=TRUE,
label.padding=unit(0.8,"mm"),label.r=unit(0.0,"mm"),label.size=0.1,size=3.5) +
## Circle
geom_node_circle(aes(r=log(size)+1),color="black",fill="white",size=0.4) +
## Plot work activity
geom_node_text(aes(size=w,hjust=log(w)+0.4),label="w",color="red",
position="identity",vjust=0.4,fontface="bold") +
## Plot school activity
geom_node_text(aes(size=s,hjust=-log(s)-0.2),label="s",color="blue",
position="identity",vjust=0.4,fontface="bold") +
## Size scale
scale_size(range=c(0,5),breaks=c(1:100),name="Numberof\nActivities",
guide=guide_legend(override.aes=list(label="a",color="black"))) +
# scale_color() +
## Theme
theme_graph() + coord_fixed()
This is my desired result.
This is the result from above scripts.
There are two issues related to legend to reach my desired result:
How can I replace overlapped "w" and "s" in "Number of Activities" by other font, such as "a" (activity) in black as shown in desired result?- How can I add one more manual legend "Types of activity" shown in desired result?
Though it is written in ggraph, I suppose the grammar seems to be similar to that in ggplot2. I appreciate your suggestions!!
========== UPDATE ==========
The first issue has solved by changing scale_size argument as shown in updated scripts.
However, the second issue is still remaining and I found one more issue on 0-value symbols at the center of circles (very small dot). I have found some solutions to solve the issue by applying 1) subset() to omit 0-value records from data frame in data=subset(df,x!=0), 2) simply filling 0 value by NA in data=ifelse(x==0,NA,.) methods, however as it is written from graph object, it may not work for this case straightforward.
========== UPDATE ver.2 ==========
It is really tricky but somehow I could remove dots at the center of line as well as adding one legend.
I am really not sure the reason but the former issue was solved by 1) replacing 0 values in node data frame by NA, 2) replace NA in aes(size=...) statement in geom_node_text as aes(size=ifelse(is.na(w),0,w) ..., then 3) specify color by color=ifelse(w==0,"white","red"). It does not remove the data but just change color of 0-value into white to make it invisible.
I suppose it is not formal solution but only the way that I encountered during dozens of trials. Interesting thing is that 1) and 2) should be combined otherwise it returns an error.
Thus this is the final update:
## Packages
library(igraph)
library(tidygraph)
library(ggraph)
library(ggplot2)
library(tidyverse)
## Edge and node
edge <- data.frame(from=c(0,0,0,0,1,2,3),
to=c(0,1,2,3,0,0,0),
weight=c(1,3,1,1,3,1,1))
node <- data.frame(id=c(0,1,2,3),
p=c(9,1,0,0),
w=c(0,2,0,0),
s=c(0,1,1,1),
size=c(9,3,1,1),
gr=c(0,1,1,2))
## Load data frames as tbl_graph class
edge <- edge %>% mutate(from=from+1,to=to+1)
# THIS IS QUITE STRANGE OPERATION FOR CHANGING COLOR
node <- node %>% mutate_at(vars(p,w,s,size),funs(ifelse(.==0,NA,.)))
net <- tbl_graph(nodes=node,edges=edge,directed=TRUE)
## Set arrows
ar <- arrow(angle=30,length=unit(5,"mm"),ends="last",type="closed")
## Plot
ggraph(net,layout="graphopt") +
## Edges
geom_edge_link(aes(start_cap=circle(log(node1.size)+2,unit="native"),
end_cap=circle(log(node2.size)+2,unit="native"),
width=weight,label=weight),
position="identity",angle_calc="along",force_flip=TRUE,
label_dodge=unit(4.0,"mm"),label_push=unit(-0.4,"mm")) +
## Width scale
scale_edge_width(range=c(0.4,4),breaks=c(1:10),name="Movements\nbetween zones") +
## Add arrows separately
geom_edge_link(arrow=ar,aes(start_cap=circle(log(node1.size)+1,unit="native"),
end_cap=circle(log(node2.size)+1,unit="native"))) +
## Nodes
## Plot location id
geom_node_label(aes(label=id,hjust=log(size+6),vjust=log(size+6)),repel=TRUE,
label.padding=unit(0.8,"mm"),label.r=unit(0.0,"mm"),label.size=0.1,size=3.5) +
## Circle
geom_node_circle(aes(r=log(size)+1),color="black",fill="white",size=0.4) +
## Plot work activity: NOT KNOW WHY IT WORKS!!
geom_node_text(aes(size=ifelse(is.na(w),0,w),hjust=log(w)+0.4,color=ifelse(w==0,"white","red")),label="w",
position="identity",vjust=0.4,fontface="bold") +
## Plot school activity
geom_node_text(aes(size=ifelse(is.na(s),0,s),hjust=-log(s)-0.2,color=ifelse(s==0,"white","blue")),label="s",
position="identity",vjust=0.4,fontface="bold") +
## Edit legend
scale_size_continuous(range=c(0,5),breaks=c(1:100),name="Numberof\nActivities",
guide=guide_legend(override.aes=list(label="a",color="black"))) +
scale_color_manual(name="Type of Activity",guide=guide_legend(override.aes=list(label=c("w","s"))),
values=c("red","blue"),labels=c("Work","School")) +
## Theme
theme_graph() + coord_fixed()
However, as it is still ugly codes, I am still waiting for your suggestions for more appropriate operations.
来源：https://stackoverflow.com/questions/51581399/manual-legend-in-ggraph-ggplot2-r