r - Replace element in vector based on first letter of character string -


consider vectors below:

id <- c("a1","b1","c1","a12","b2","c2","av1")  names <- c("alpha","bravo","charlie","avocado")

i want replace first character of each element in vector id vector names based on first letter of vector names. want add _0 before each number between 0:9.

note elements av1 , avocado throw things off bit, lowercase v in av1.

the result should this:

res <- c("alpha_01","bravo_01","charlie_01","alpha_12","bravo_02","charlie_02", "avocado_01")

i know should done regex i've been trying 2 days , haven't got anywhere.

we can use gsubfn.

library(gsubfn) #remove number part 'id' (using `sub`) , unique elements nm1 <- unique(sub("\\d+", "", id)) #using gsubfn, replace non-numeric elements matching  #key/value pair in replacement #finally format add "_" sub sub("(\\d+)$", "_0\\1", gsubfn("(\\d+)", as.list(setnames(names, nm1)), id)) #[1] "alpha_01"   "bravo_01"   "charlie_01" "alpha_02"  #[5] "bravo_02"   "charlie_02" "avocado_01"

the (\\d+) indicates 1 or more numeric elements, , (\\d+) 1 or more non-numeric elements. wrapping within brackets capture group , replace backreference (\\1 - first backreference captured group).

update

if condition append 0 'id's have numbers less 10, can second gsubfn , sprintf

gsubfn("(\\d+)", ~sprintf("_%02d", as.numeric(x)),                        gsubfn("(\\d+)", as.list(setnames(names, nm1)), id)) #[1] "alpha_01"   "bravo_01"   "charlie_01" "alpha_12"  #[5]  "bravo_02"   "charlie_02" "avocado_01"

-

Comments

Post a Comment

Popular posts from this blog

unity3d - Rotate an object to face an opposite direction -

i have object , b. when click on object b, rotates object b (a faces b). b doesn't face a. need following : when faces b, need face opposite direction. have code rotating @ b. how rotate face opposite direction after that? vector3 targetdirection = target - transform.position; float step = speed * time.deltatime; vector3 newdirection = vector3.rotatetowards (turretdome.transform.forward, targetdirection, step, 0.0f); turretdome.transform.rotation = quaternion.lookrotation (newdirection); you object facing object b, want inverse direction of object after that? objecta.transform.rotation = quaternion.inverse(objecta.transform.rotation) but lets assume example turretdome object a, (negate direction): turretdome.transform.rotation = quaternion.lookrotation (-newdirection); naturally, both of these snippets not show how smoothen rotation, seem know how use time.deltatime. just incase unsure, quaternion.lerp this
Read more

angular - Is it possible to get native element for formControl? -

i've got angular2 reactive form . created formcontrol s , assigned input fields by [formcontrol]=... . understand creates nativeelement <-> formcontrol link. my question: possible nativeelement formcontrol ? wanna myformcontrol.nativeelement.focus() i can share 1 terrible solution works me. in reactive forms can use either 1) formcontroldirective ts mycontrol = new formcontrol('') template <input type="text" [formcontrol]="mycontrol"> or 2) formcontrolname ts myform: formgroup; constructor(private fb: formbuilder) {} ngoninit() { this.myform = this.fb.group({ foo: '' }); } template <form [formgroup]="myform"> <input type="text" formcontrolname="foo"> </form> so these directives write patch like 1) formcontroldirective const originformcontrolngonchanges = formcontroldirective.prototype.ngonchanges; formcontroldirective.proto
Read more

javascript - Why jQuery Select box change event is now working? -

i working on product filters user select select box according his/her preference not getting selected value user in jquery. html code:- <select name="product_filter" id="product_filter"> <option value="price_low_first">price : low high</option> <option value="price_high_first">price : high low</option> <option value="latest">latest</option> <option value="popular">most popular</option> </select> jquery code: $(function () { $("#product_filter").change(function () { alert("hi") var selectedtext = $(this).find("option:selected").text(); var selectedvalue = $(this).val(); alert("selected text: " + selectedtext + " value: " + selectedvalue); }); }); hi believe code perfect. once please check jquery.min.js
Read more