Easy way to map values using intervals stored as strings in R?

Question

I have a dataframe of intervals stored as strings :

                interval
1       '(-inf-57142.8]'
2    '(57142.8-94002.6]'
3   '(94002.6-130862.4]'
4  '(130862.4-167722.2]'
5    '(167722.2-204582]'
6    '(204582-241441.8]'
7  '(241441.8-278301.6]'
8  '(278301.6-315161.4]'
9  '(315161.4-352021.2]'
10      '(352021.2-inf)'

I want to map any given number to interval "bins", using the intervals stored in the dataframe above and the index as the bin number i.e.

-57142.8 would map to 1

-57142.9 would map to 2

130862.5 would map to 4

352021.2 would map to 9

352021.3 would map to 10

etc

The intervals are generated dynamically using a discretize function.

Are there any simple R tools for helping to achieve this?

Or anything that deals with intervals stored as strings?

Thanks In Advance

You should include the other data.frames you are using, and an example of the desired output. — rpolicastro, Sep 21 '20 at 18:35

score 0 · Answer 1 · answered Sep 22 '20 at 13:39

Resolved this using gsub & findInterval, It may be useful to others?

Get boundary from strings described in original question above :

  boundaries<-gsub("\\(-inf-|\\(-inf-|\\(\\d+[.]*\\d+[-]+|\\'|\\]","",intervals$interval)[1:9] %>% as.numeric()

Get Interval position:

findInterval(value_to_test,boundaries[1:9],rightmost.closed = FALSE,all.inside = TRUE)

The endpoints '(-inf-57142.8]' & '(352021.2-inf)' are dealt with seperately as special cases. If the value_to_test lands on a boundary its Interval position is also a special case and adjusted by -1.

Easy way to map values using intervals stored as strings in R?

1 Answers1