R: Gmisc / Grid and alignment of boxes

Question

I would like to create a dynamic flow-chart using "Gmisc", "grid", and lists in R.

Basically the code looks as follows:

##############################

library(Gmisc)
library(grid)

# list of names
a.names <- list("i1", "i2", "i3")

# list of boxes
a <- list(boxGrob("item 1"), 
          boxGrob("item 2"), 
          boxGrob("item 3")
)
# asigning names to list
names(a) <- a.names

# spreading boxes
b <- spreadHorizontal(a)
names(b) <- (a.names)

# clear view
grid.newpage()

# print boxes spread horizontal
b

Now, a second list of boxes should be aligned vertically along the first box (Item 1).

using

alignHorizontal(reference = b$i1, a) %>% spreadVertical(.from = 0.9, .to=0.6)

results in an error, while

dummy <- b$i2
temp <- alignHorizontal(reference = dummy, a$i1, a$i2) 
spreadVertical(temp, .from=0.9, .to=0.6)

works fine, and

dummy <- b$i3
temp <- alignHorizontal(reference = dummy, a) 
spreadVertical(temp, .from=0.9, .to=0.6)

results in an error. Obviously, the alignHorizontal needs single elements and cannot deal with a list of elements. Is there any chance to hand over a list of boxes to that function?

Sincerely, Steffen

score 0 · Answer 1 · answered Jun 02 '22 at 20:22

One option to pass your list would be to use do.call like so:

library(Gmisc)
#> Loading required package: Rcpp
#> Loading required package: htmlTable
library(grid)

# list of names
a.names <- list("i1", "i2", "i3")

# list of boxes
a <- list(
  boxGrob("item 1"),
  boxGrob("item 2"),
  boxGrob("item 3")
)
# asigning names to list
names(a) <- a.names

# spreading boxes
b <- spreadHorizontal(a)
names(b) <- (a.names)

# clear view
grid.newpage()

# print boxes spread horizontal
b

do.call(alignHorizontal, c(list(reference = b$i1), a)) |>
  spreadVertical(.from = 0.9, .to = 0.6)

R: Gmisc / Grid and alignment of boxes

1 Answers1