update_prop calls user-specified methods to get properties
of a source set of elements in a data set, combine those properties,
and set the properties of a target element to the combined value.
If the source set is empty, the data set is returned unmodified. The
default combine operation is addition.
The override argument can be used to selectively override the
computed value based on the target element. By default, it simply
returns the value computed by the combiner.
Usage
update_prop(
ds,
target,
sources,
set,
get,
combine = function(l) Reduce("+", l),
override = function(ds, target, v) v
)Arguments
- ds
data set to be updated
- target
key of data set element to be updated
- sources
keys of data set elements to be combined
- set
function to set properties for a target element called as set(ds, key, value)
- get
function to get properties for source elements called as get(ds, key)
- combine
function to combine properties called as combine(vl)
- override
function to selectively override combined results called as override(ds, key,)
Examples
update_prop(wbs_table, "1", list("1.1", "1.2"),
function(d, k, v) {d[d$id == k, "work"] <- v; d},
function(d, k) d[d$id == k, "work"]
)
#> id pid name work budget
#> 1 top <NA> Construction of a House NA NA
#> 2 1 top Internal 45.6 NA
#> 3 2 top Foundation NA NA
#> 4 3 top External NA NA
#> 5 1.1 1 Electrical 11.8 25000
#> 6 1.2 1 Plumbing 33.8 61000
#> 7 2.1 2 Excavate 18.2 37000
#> 8 2.2 2 Steel Erection 5.8 9000
#> 9 3.1 3 Masonry Work 16.2 62000
#> 10 3.2 3 Building Finishes 14.2 21500
update_prop(wbs_table, "1", list("1.1", "1.2"),
function(d, k, v) {d[d$id == k, c("work", "budget")] <- v; d},
function(d, k) d[d$id == k, c("work", "budget")],
function(l) Reduce("+", l)
)
#> id pid name work budget
#> 1 top <NA> Construction of a House NA NA
#> 2 1 top Internal 45.6 86000
#> 3 2 top Foundation NA NA
#> 4 3 top External NA NA
#> 5 1.1 1 Electrical 11.8 25000
#> 6 1.2 1 Plumbing 33.8 61000
#> 7 2.1 2 Excavate 18.2 37000
#> 8 2.2 2 Steel Erection 5.8 9000
#> 9 3.1 3 Masonry Work 16.2 62000
#> 10 3.2 3 Building Finishes 14.2 21500