I would like to clean this vector and only retain the digits
vec = c(" 4010 \"Filling in time budget diary\"", " 8888 \"Prob cont. preceding activity\"", " 9999 \"Missing, undecipherable\";")
what I would like is simply : 4010, 8888, 9999
I thought of something like, matching exactly the digits but it doesn't work.
gsub("^[[:digit:]]$", replacement = '', vec)
Thanks
We can use \\D+ to match all non-numeric elements and replace with ''
gsub('\\D+','', vec)
Related
I'm trying to write a Ruby method that will return true only if the input is a valid phone number, which means, among other rules, it can have spaces and/or dashes between the digits, but not before or after the digits.
In a sense, I need a method that does the opposite of String#strip! (remove all spaces except leading and trailing spaces), plus the same for dashes.
I've tried using String#gsub!, but when I try to match a space or a dash between digits, then it replaces the digits as well as the space/dash.
Here's an example of the code I'm using to remove spaces. I figure once I know how to do that, it will be the same story with the dashes.
def valid_phone_number?(number)
phone_number_pattern = /^0[^0]\d{8}$/
# remove spaces
number.gsub!(/\d\s+\d/, "")
return number.match?(phone_number_pattern)
end
What happens is if I call the method with the following input:
valid_phone_number?(" 09 777 55 888 ")
I get false because line 5 transforms the number into " 0788 ", i.e. it gets rid of the digits around the spaces as well as the spaces. What I want it to do is just to get rid of the inner spaces, so as to produce " 0977755888 ".
I've tried
number.gsub!(/\d(\s+)\d/, "") and number.gsub!(/\d(\s+)\d/) { |match| "" } to no avail.
Thank you!!
If you want to return a boolean, you might for example use a pattern that accepts leading and trailing spaces, and matches 10 digits (as in your example data) where there can be optional spaces or hyphens in between.
^ *\d(?:[ -]?\d){9} *$
For example
def valid_phone_number?(number)
phone_number_pattern = /^ *\d(?:[ -]*\d){9} *$/
return number.match?(phone_number_pattern)
end
See a Ruby demo and a regex demo.
To remove spaces & hyphen inbetween digits, try:
(?:\d+|\G(?!^)\d+)\K[- ]+(?=\d)
See an online regex demo
(?: - Open non-capture group;
d+ - Match 1+ digits;
| - Or;
\G(?!^)\d+ - Assert position at end of previous match but (negate start-line) with following 1+ digits;
)\K - Close non-capture group and reset matching point;
[- ]+ - Match 1+ space/hyphen;
(?=\d) - Assert position is followed by digits.
p " 09 777 55 888 ".gsub(/(?:\d+|\G(?!^)\d+)\K[- ]+(?=\d)/, '')
Prints: " 0977755888 "
Using a very simple regex (/\d/ tests for a digit):
str = " 09 777 55 888 "
r = str.index(/\d/)..str.rindex(/\d/)
str[r] = str[r].delete(" -")
p str # => " 0977755888 "
Passing a block to gsub is an option, capture groups available as globals:
>> str = " 09 777 55 888 "
# simple, easy to understand
>> str.gsub(/(^\s+)([\d\s-]+?)(\s+$)/){ "#$1#{$2.delete('- ')}#$3" }
=> " 0977755888 "
# a different take on #steenslag's answer, to avoid using range.
>> s = str.dup; s[/^\s+([\d\s-]+?)\s+$/, 1] = s.delete("- "); s
=> " 0977755888 "
Benchmark, not that it matters that much:
n = 1_000_000
puts(Benchmark.bmbm do |x|
# just a match
x.report("match") { n.times {str.match(/^ *\d(?:[ -]*\d){9} *$/) } }
# use regex in []=
x.report("[//]=") { n.times {s = str.dup; s[/^\s+([\d\s-]+?)\s+$/, 1] = s.delete("- "); s } }
# use range in []=
x.report("[..]=") { n.times {s = str.dup; r = s.index(/\d/)..s.rindex(/\d/); s[r] = s[r].delete(" -"); s } }
# block in gsub
x.report("block") { n.times {str.gsub(/(^\s+)([\d\s-]+?)(\s+$)/){ "#$1#{$2.delete('- ')}#$3" }} }
# long regex
x.report("regex") { n.times {str.gsub(/(?:\d+|\G(?!^)\d+)\K[- ]+(?=\d)/, "")} }
end)
Rehearsal -----------------------------------------
match 0.997458 0.000004 0.997462 ( 0.998003)
[//]= 1.822698 0.003983 1.826681 ( 1.827574)
[..]= 3.095630 0.007955 3.103585 ( 3.105489)
block 3.515401 0.003982 3.519383 ( 3.521392)
regex 4.761748 0.007967 4.769715 ( 4.772972)
------------------------------- total: 14.216826sec
user system total real
match 1.031670 0.000000 1.031670 ( 1.032347)
[//]= 1.859028 0.000000 1.859028 ( 1.860013)
[..]= 3.074159 0.003978 3.078137 ( 3.079825)
block 3.751532 0.011982 3.763514 ( 3.765673)
regex 4.634857 0.003972 4.638829 ( 4.641259)
I have a dataframe column including pages paths :
pagePath
/text/other_text/123-some_other_txet-4571/text.html
/text/other_text/another_txet/15-some_other_txet.html
/text/other_text/25189-some_other_txet/45112-text.html
/text/other_text/text/text/5418874-some_other_txet.html
/text/other_text/text/text/some_other_txet-4157/text.html
What I want to do is to extract the first number after a /, for example 123 from each row.
To solve this problem, I tried the following :
num = gsub("\\D"," ", mydata$pagePath) /*to delete all characters other than digits */
num1 = gsub("\\s+"," ",num) /*to let only one space between numbers*/
num2 = gsub("^\\s","",num1) /*to delete the first space in my string*/
my_number = gsub( " .*$", "", num2 ) /*to select the first number on my string*/
I thought that what's that I wanted, but I had some troubles, especially with rows like the last row in the example : /text/other_text/text/text/some_other_txet-4157/text.html
So, what I really want is to extract the first number after a /.
Any help would be very welcome.
You can use the following regex with gsub:
"^(?:.*?/(\\d+))?.*$"
And replace with "\\1". See the regex demo.
Code:
> s <- c("/text/other_text/123-some_other_txet-4571/text.html", "/text/other_text/another_txet/15-some_other_txet.html", "/text/other_text/25189-some_other_txet/45112-text.html", "/text/other_text/text/text/5418874-some_other_txet.html", "/text/other_text/text/text/some_other_txet-4157/text.html")
> gsub("^(?:.*?/(\\d+))?.*$", "\\1", s, perl=T)
[1] "123" "15" "25189" "5418874" ""
The regex will match optionally (with a (?:.*?/(\\d+))? subpattern) a part of string from the beginning till the first / (with .*?/) followed with 1 or more digits (capturing the digits into Group 1, with (\\d+)) and then the rest of the string up to its end (with .*$).
NOTE that perl=T is required.
with stringr str_extract, your code and pattern can be shortened to:
> str_extract(s, "(?<=/)\\d+")
[1] "123" "15" "25189" "5418874" NA
>
The str_extract will extract the first 1 or more digits if they are preceded with a / (the / itself is not returned as part of the match since it is a lookbehind subpattern, a zero width assertion, that does not put the matched text into the result).
Try this
\/(\d+).*
Demo
Output:
MATCH 1
1. [26-29] `123`
MATCH 2
1. [91-93] `15`
MATCH 3
1. [132-137] `25189`
MATCH 4
1. [197-204] `5418874`
I am trying to gsub exact FULL string - I know I need to use ^ and $. The problem is that I have special characters in strings (could be [, or .) so I need to use fixed=T. This overrides the ^ and $. Any solution is appreciated.
Need to replace 1st, 2nd element in exact_orig with 1st, 2nd element from exact_change but only if full string is matched from beginning to end.
exact_orig = c("oz","32 oz")
exact_change = c("20 oz","32 ct")
gsub_FixedTrue <- function(i) {
for(k in seq_along(exact_orig)) i = gsub(exact_orig[k],exact_change[k],i,fixed=TRUE)
return(i)
}
Test cases:
print(gsub_FixedTrue("32 oz")) #gives me "32 20 oz" - wrong! Must be "32 ct"
print(gsub_FixedTrue("oz oz")) # gives me "20 oz 20 oz" - wrong! Must remain as "oz oz"
I read a somewhat similar thread, but could not make it work for full string (grep at the beginning of the string with fixed =T in R?)
If you want to exactly match full strings, i don't think you really want to use regular expressions in this case. How about just the match() function
fixedTrue<-function(x) {
m <- match(x, exact_orig)
x[!is.na(m)] <- exact_change[m[!is.na(m)]]
x
}
fixedTrue(c("32 oz","oz oz"))
# [1] "32 ct" "oz oz"
I am not familiar at all with regular expressions, and would like to do pattern matching and replacement in R.
I would like to replace the pattern #1, #2 in the vector: original = c("#1", "#2", "#10", "#11") with each value of the vector vec = c(1,2).
The result I am looking for is the following vector: c("1", "2", "#10", "#11")
I am not sure how to do that. I tried doing:
for(i in 1:2) {
pattern = paste("#", i, sep = "")
original = gsub(pattern, vec[i], original, fixed = TRUE)
}
but I get :
#> original
#[1] "1" "2" "10" "11"
instead of: "1" "2" "#10" "#11"
I would appreciate any help I can get! Thank you!
Specify that you are matching the entire string from start (^) to end ($).
Here, I've matched exactly the conditions you are looking at in this example, but I'm guessing you'll need to extend it:
> gsub("^#([1-2])$", "\\1", original)
[1] "1" "2" "#10" "#11"
So, that's basically, "from the start, look for a hash symbol followed by either the exact number one or two. The one or two should be just one digit (that's why we don't use * or + or something) and also ends the string. Oh, and capture that one or two because we want to 'backreference' it."
Another option using gsubfn:
library(gsubfn)
gsubfn("^#([1-2])$", I, original) ## Function substituting
[1] "1" "2" "#10" "#11"
Or if you want to explicitly use the values of your vector , using vec values:
gsubfn("^#[1-2]$", as.list(setNames(vec,c("#1", "#2"))), original)
Or formula notation equivalent to function notation:
gsubfn("^#([1-2])$", ~ x, original) ## formula substituting
Here's a slightly different take that uses zero width negative lookahead assertion (what a mouthful!). This is the (?!...) which matches # at the start of a string as long as it is not followed by whatever is in .... In this case two (or equivalently, more as long as they are contiguous) digits. It replaces them with nothing.
gsub( "^#(?![0-9]{2})" , "" , original , perl = TRUE )
[1] "1" "2" "#10" "#11"
I want to match a number containing 17-23 digits interspersed with spaces or hyphens, then replace all but the last five digits with asterisks. I can match with the following regex:
((?:(?:\d)([\s-]*)){12,18})(\d[\s-]*){5}
My problem is that I can't get the regex to group all instances of [\s-] in the first section, and I have no idea how to get it to replace the initial 12-18 digits with asterisks (*).
How about this:
s/\d(?=(?:[ -]*\d){5,22}(?![ -]*\d))/*/g
The positive lookahead insures that there are at least 5 digits ahead of the just-matched digit, while the embedded negative lookahead insures that aren't more than 22.
However, there could still be more digits before the first-matched digit. That is, if there are 24 or more digits, this regex only operates on the last 23 of them. I don't know if that's a problem for you.
Even assuming that this is feasible with regex alone I'd bet that it would be way slower than using the non-capturing version of your regex and then reverse iterating over the match, leaving the first 5 digits alone and replacing the rest of them with '*'.
I think your regex is ok, but you might need to have a callback where you can insert the asterisks with another inline regex. The below is a Perl example.
s/((?:\d[\s-]*){12,18})((?:\d[\s-]*){4}\d)/ add_asterisks($1,$2) /xeg
use strict;
use warnings;
my $str = 'sequence of digits 01-2 3-456-7-190 123-416 78 ';
if ($str =~ s/((?:\d[\s-]*){12,18})((?:\d[\s-]*){4}\d)/ add_asterisks($1,$2) /xeg )
{
print "New string: '$str'\n";
}
sub add_asterisks {
my ($pre,$post) = #_;
$pre =~ s/\d/*/g;
return $pre . $post;
}
__END__
Output
New string: 'sequence of digits **-* *-***-*-*** ***-416 78 '
To give a java regex variant to Alan Moore's answer and using all word characters [a-zA-Z0-9] as \w instead of just digits \d.
This will also work with any length string.
public String maskNumber(String number){
String regex = "\\w(?=(?:\\W*\\w){4,}(?!\\W*\\w))";
Pattern p = Pattern.compile(regex);
Matcher m = p.matcher(number);
while(m.find()){
number = number.replaceFirst(m.group(),"*");
}
return number;
}
This example
String[] numbers = {
"F4546-6565-55654-5457",
"F4546-6565-55654-54-D57",
"F4546-6565-55654-54-D;5.7",
"F4546-6565-55654-54-g5.37",
"hd6g83g.duj7*ndjd.(njdhg75){7dh i8}",
"####.####.####.675D-45",
"****.****.****.675D-45",
"**",
"12"
};
for (String number : numbers){
System.out.println(maskNumber(number));
}
Gives:
*****-****-*****-5457
*****-****-*****-*4-D57
*****-****-*****-*4-D;5.7
*****-****-*****-**-g5.37
*******.*********.(*******){*dh i8}
####.####.####.**5D-45
****.****.****.**5D-45
**
12