labeling_cells function with 2d mosaic

Question

There seems to be something (many things?) I don't understand about how to use mosaic in package vcd and labeling_cells because I keep getting an error.

Setup:

I have a 2d array of values (row and column names changed to protect the innocent):

tmparray
       C1    C2   C3    C4    C5    C6
P1  65241 15534 5754 12747 57902 48367
P2    205 28581 4819  7617  5504 34656
P3     27  3503 1473   757  3308 15363
P4 417580  5967 5353   636   514  9758
P5  31482   915  249   914   328  1301
P6  75501  4307  294   176    27  8376
P7  43589  2864  465   179    61 12631
P8  64095  1008  335   288     3  7438

mosaic(tmparray) gets me the expected plot (rep too low to post image).

I would like to add text labels for each cell showing only the values in tmparray > 1000 . Following the documentation for labeling_cells , I try the following:

celltxt <- ifelse(tmparray < 1000, NA, tmparray/1000)
celltxt
        C1     C2    C3     C4     C5     C6
P1  65.241 15.534 5.754 12.747 57.902 48.367
P2      NA 28.581 4.819  7.617  5.504 34.656
P3      NA  3.503 1.473     NA  3.308 15.363
P4 417.580  5.967 5.353     NA     NA  9.758
P5  31.482     NA    NA     NA     NA  1.301
P6  75.501  4.307    NA     NA     NA  8.376
P7  43.589  2.864    NA     NA     NA 12.631
P8  64.095  1.008    NA     NA     NA  7.438

labeling_cells(text = celltxt)(tmparray)

Which results in the following error:

# Error in ifelse(abbreviate_varnames, sapply(seq_along(dn), function(i) abbreviate(dn[i],  : replacement has length zero

Can anyone please point out how to get the labeling to work?

Answer 1

OK, so I'm assuming class(tmparray)=="matrix" . That seems to be fine for plotting, but it looks like if you want to use labeling_cells you're going to want to convert that to a table, being sure to add named dimensions. You can do that with

tmparray <- as.table(tmparray)
names(dimnames(tmparray))<-c("P","C")

So when you create celltext now with

celltxt <- ifelse(tmparray < 1000, NA, tmparray/1000)

It will also be a table with the same dimnames .

The other important thing you must do is pass pop=F to mosaic . This will leave the grid viewport structure in place so that the labeling_cells function can find the correct locations for the labels. So you can create the plot with

mosaic(tmparray , pop=F)
labeling_cells(text = celltxt, margin=0)(tmparray)

Which results in

(I did round the values to one decimal place to try to make things a bit neater)