acol: Column Numbers Within the Augmented Row-Column Grid for a Table

Description

Return the column numbers associated with a specified table part or element, or with a set of column header values, within the augmented row-column grid of a table.

Usage

acol(x, id=NULL, hpath=NULL)

Value

A numeric vector containing column numbers within the table's augmented row-column grid. The column numbers are those partially or completely occupied by the cells associated with id or hpath. They will be increasing but not necessarily consecutive.

The returned vector may have length 0 if id refers to a table part or block that spans no columns, or if hpath matches no set of column header values.

Note that for a vertical hvrule (vrule), the "column number" is actually a half-integer, bracketed by the table column numbers between which the vrule runs. For example, if the vrule runs between table columns 3 and 4, the returned value will be c(3.5).

Arguments

x: A textTable or a plotted table (pltdTable) object.
id: Character scalar containing the ID of a single table part, block, entry, or hvrule. (If x is a textTable, only the ID of a table part is allowed.)
hpath: Character vector with length between 0 and the number of layers in the column header. The i-th element should be one of the values in the i-th header row, or NA. See DETAILS. Only one of id and hpath should be specified.

Details

See the documentation for adim for more information about the augmented row-column grid of a table.

Only one of arguments id and hpath should be specified. id is searched for first among table parts (the only thing available for a textTable), then blocks, entries, and hvrules, in that order. The search stops at the first match. It is an error if id is not found in any of these.

hpath is short for "header path". It is used to obtain column numbers associated with specified combinations of values of the column header variables. Suppose there are L layers of column headers. If the length of hpath is less than L, NA values are added at the end to reach that length. The function returns the intersection of the column numbers for which the i-th outermost of the header layers equals the i-th element of hpath. An NA in hpath is taken to match all values in the correponding layer of column headers. Thus, if L == 4 and hpath=c("a", NA, "c"), the function will return the column numbers for which the outermost column header has a value of "a" _and_ the third outermost has a value of "c". If no column has the combination of values specified by hpath then the returned vector will have length 0.

Since hpath refers to values of column header variables, it cannot be used to get column numbers associated with table annotation, or with the row header. (Use id instead.)

Examples

Run this code

ttbl <- textTable(iris2_tab, title=c("Title 1", "2nd title"), foot="Foot")
plt <- plot(ttbl)

acol(plt, id="title")  # block "title" spans all columns
acol(plt, id="body,4,2")  # single entry
# Remove the columns for "Petal" measurements (a value in column 
# header layer 2):
plot(ttbl[, -acol(ttbl, hpath=c(NA, "Petal"))])
# Remove the "Length" measurements (a value in column header layer 3):
plot(ttbl[, -acol(ttbl, hpath=c(NA, NA, "Length"))])
# Remove the "Length" measurements just for "Petal":
plot(ttbl[, -acol(ttbl, hpath=c(NA, "Petal", "Length"))])