Home/ Questions/Q 7574875
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-30T16:32:37+00:00

I need to apply function to vector b3, but insert 0 (and do not

  • 0

I need to apply function to vector b3, but insert 0 (and do not apply function) when b3 < 0.

> b3
 [1]  1.5  0.5  5.5  0.5  9.5  8.5  4.5  3.5  3.5  3.5  1.5 -0.5  1.5  5.5  9.5
[16]  5.5  2.5  1.5  2.5  3.5  9.5 -0.5  4.5  2.5  1.5  4.5 -0.5 -0.5  1.5  0.5

> unlist(lapply(b3, function(x) {seq(from = 0.5, to = x)})) 
  [1]  0.5  1.5  0.5  0.5  1.5  2.5  3.5  4.5  5.5  0.5  0.5  1.5  2.5  3.5  4.5
 [16]  5.5  6.5  7.5  8.5  9.5  0.5  1.5  2.5  3.5  4.5  5.5  6.5  7.5  8.5  0.5
 [31]  1.5  2.5  3.5  4.5  0.5  1.5  2.5  3.5  0.5  1.5  2.5  3.5  0.5  1.5  2.5
 [46]  3.5  0.5  1.5  0.5 -0.5  0.5  1.5  0.5  1.5  2.5  3.5  4.5  5.5  0.5  1.5
 [61]  2.5  3.5  4.5  5.5  6.5  7.5  8.5  9.5  0.5  1.5  2.5  3.5  4.5  5.5  0.5
 [76]  1.5  2.5  0.5  1.5  0.5  1.5  2.5  0.5  1.5  2.5  3.5  0.5  1.5  2.5  3.5
 [91]  4.5  5.5  6.5  7.5  8.5  9.5  0.5 -0.5  0.5  1.5  2.5  3.5  4.5  0.5  1.5
[106]  2.5  0.5  1.5  0.5  1.5  2.5  3.5  4.5  0.5 -0.5  0.5 -0.5  0.5  1.5  0.5

gives me close to what I need, but I have problems with negatives values of b3. So how to introduce 0 each times function get to negative value in b3 ? Here’s what I came with : 

> unlist(lapply(b3, function(x) {ifelse(x>0,seq(from = 0.5, to = x),0)}))
 [1] 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5
[20] 0.5 0.5 0.0 0.5 0.5 0.5 0.5 0.0 0.0 0.5 0.5

works for negative values, but my function doesn’t behave as expected…

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    Sorry for the previous answer, I read too quickly. You probably just want to use if rather than ifelse:

    #Small, similar example
b3 <- c(1.5,0.5,5.5,-2.5,1.5)
unlist(lapply(b3, function(x) {if (x < 0) 0 else seq(from = 0.5, to = x)}))
[1] 0.5 1.5 0.5 0.5 1.5 2.5 3.5 4.5 5.5 0.0 0.5 1.5
    • 0