Ideas for improving the print method

[karoliskoncevicius]

This issue is dedicated for collecting ideas about improvements to annmatrix print method.

Currently print.annmatrix does quite a good job of displaying annmatrix and possible annotations in a compact form:

X

             [,1]        [,2]        [,3]        [,4]                    [,6]
 [1,] -0.66184983 -0.38282188 -1.26681476 -1.42199245 ........... -1.86544873
 [2,]  1.71895416  0.29942160 -0.19858329 -0.32822829 ...........  1.82998433
 [3,]  2.12166699  0.67423976  0.13886578  0.28457007 ........... -0.99111590
 [4,]  1.49715368 -0.29281632 -0.27933600  0.71933588 ........... -1.45043462
      ........... ........... ........... ........... ........... ...........
[10,]  1.04318309  1.08808601 -1.42776759  0.01587026 ........... -0.14174471

rann: chr, pos
cann: group, sex

However, it doesn't show anything about the types or actual values of those annotations.
Maybe it would be possible to add them nicely somewhere, similar to what @HenrikBengtsson did in his Wishlist-for-R:

X

     male female
       43     28
        B      C
[1,]    4      7
[2,]    5      8
[3,]    6      9

Seems like this would only work for a small number of short annotations and it might be tricky to get it right in practice.
Here is one prototype with a small amount of annotations:

                        sex       "F"        "M"       "F" 
                        age        22         39        73
                      group    "case"  "control"    "case"

 chr     position                [,1]       [,2]      [,3]
 "chr1"    100103      [1,]      20.3       17.2        10
 "chr1"    100203      [2,]        13        0.5      -0.1
 "chr2"      3030      [3,]       9.3        1.1      10.5
 "chr3"     14140      [4,]        -4          0      22.2

But in general case both the number of annotations and the annotation entry lengths might have to be truncated.