The problem:
===========
Once a dendrogram has a branch with both a line type AND a color (which is
a character color), the plot.dendrogram function will not plot and return
an error.
I say this is a bug because (I believe), we would like a dendrogram to be
able to use character colors, while also allowing control over line types.
This e-mail includes an example, and what I think a solution might be.
Reproducible example:
=================
install.packages('dendextend')
library('dendextend')
dend <- 1:2 %>% dist %>% hclust %>% as.dendrogram
plot(dend) # works fine
dend %>% set("branches_lty", 1:2) %>% plot # works fine
dend %>% set("branches_col", 1:2) %>% plot # works fine
dend %>% set("branches_col", as.character(1:2)) %>% plot # works fine
# Fails:
dend %>% set("branches_lty", 1:2) %>% set("branches_col",
as.character(1:2)) %>% plot
### Error:
# Error in segments(x0, y0, x1, y1, col = col, lty = lty, lwd = lwd) :
# invalid line type: must be length 2, 4, 6 or 8
# This is because edgePar has to hold both "lty" and "col"
# Since "col" is a character, it forces "lty" to become a character also.
dend %>% set("branches_lty", 1:2) %>% set("branches_col",
as.character(1:2)) %>%
unclass %>% str
Possible solution
==============
The simplest (and backward) compatible solution I can think of is to edit
the function:
stats:::plotNode
And change the following lines:
col <- Xtract("col", ePar, default = par("col"),
i)
lty <- Xtract("lty", ePar, default = par("lty"),
i)
lwd <- Xtract("lwd", ePar, default = par("lwd"),
i)
With:
col <- Xtract("col", ePar, default = par("col"),
i)
lty <- as.numeric(Xtract("lty", ePar, default = par("lty"),
i))
lwd <- as.numeric(Xtract("lwd", ePar, default = par("lwd"),
i))
With regards,
Tal
[[alternative HTML version deleted]]
______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
