[R] ggraph and changing colors in geom_node_arc_bar

[Rui Barradas]

Hello,

Try a scale_fill_gradient*, there are several.


l + geom_node_arc_bar(aes(fill = depth)) +
   scale_fill_gradient(low = "gray80", high = "gray20") +
   coord_fixed() +
   theme(legend.position = "none")


This will map increasing values of the 'fill' aesthetics to colors 
between those limits, 'gray80' (lighter) and 'gray20' (darker).


Hope this helps,

Rui Barradas

Às 18:34 de 23/04/20, Monica Palaseanu-Lovejoy escreveu:
> Hi,
> 
> I am not sure if anybody was able to tackle this subject, but finally after
> hours of trolling the internet i came to this quite ugly solution - which
> is partial but at least it changes the colors.
> So, without further ado here you go:
> 
> library(tidygraph)
> library(tidyverse)
> library(ggraph)
> library(igraph)
> # i hope i remembered all the pertinent libraries i needed.
> 
> gr <- graph_from_data_frame(flare$edges, vertices = flare$vertices)
> 
> palette1 <- colorRampPalette(c("darkviolet","orange", "forestgreen",
> "blue","black"))
> 
> hex <- palette1(252)
> 
> gr<- as_tbl_graph(gr)
> 
> gr <- gr %>%
>      activate(nodes) %>%
>      mutate(hex = ifelse(name, as.character(myHSB$hex)[shortName], NA)) %>%
>      activate(edges) %>%
>      mutate(hex = .N()$hex[to] == 'hex')
> 
> gr1 <- gr
> gr1 <- gr1 %>%
>      activate(nodes) %>%
> mutate(hex=palette1(252)) %>%
> activate(edges) %>%
> mutate(hex=palette1(251))
> 
> laygr<- create_layout(gr1, layout = 'partition', circular=TRUE)
> 
> colsgr <- laygr$hex
> 
> ggraph(gr1, layout = 'partition', circular = TRUE) +
>      geom_node_arc_bar(aes(fill=hex))+
> scale_fill_manual(values=colsgr)+
> scale_color_manual(values=colsgr)+
> theme_graph(background="grey20", border=FALSE)+
> theme(legend.position="none")
> 
> This code does actually changes the node colors, although it is still not
> very clear in which order .... i tried different orders / sort solutions,
> none very exciting. But i did change the colors. If you have other ideas
> how to do it, i will very much welcome it.
> 
> Thanks,
> Monica
> 
> 
> 
> On Wed, Apr 22, 2020 at 8:31 AM Monica Palaseanu-Lovejoy <
> monicapalalovejoy using gmail.com> wrote:
> 
>> Hi,
>>
>> I am playing with the ggraph that is amazing. But i don't quite understand
>> some of the options it has. For example:
>>
>> gr <- graph_from_data_frame(flare$edges, vertices = flare$vertices)
>>
>> l <- ggraph(gr, layout = 'partition', circular = TRUE)
>> l + geom_node_arc_bar(aes(fill = depth)) +
>>      coord_fixed()
>>
>> This will give a nice graph in shades of blue.
>> But if i want to change the fill aesthetic with a grey scale for example:
>>
>> l + geom_node_arc_bar(aes(fill = grey(seq(0,1,length=252)))) +
>>      coord_fixed() +
>> theme(legend.position = "none")
>>
>> This will give a graphic with set colors that definitely are not on a grey
>> scale. So i am missing a piece in my code.
>> I tried to add scale_edge_fill_manual(values= grey(seq(0,1,length=252)))
>> but to no avail, and besides this has to do with edges and not nodes. So
>> this is not the solution.
>>
>> What i am doing wrong, or what i am missing from my command?
>>
>> Also i am interested how the graph and ggraph plots, in the sense in what
>> order is the data plotted? I am interested in that because i may want to
>> set up either colors or widths of edges separately from my graph data for
>> visualization.
>>
>> Thanks,
>> Monica
>>
>>
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>