How to Remove a Comma Off the End of a String

How do I remove a comma off the end of a string?

$string = rtrim($string, ',');

Docs for rtrim here

Remove last comma (and possible whitespaces after the last comma) from the end of a string

This will remove the last comma and any whitespace after it:

str = str.replace(/,\s*$/, "");

It uses a regular expression:

The / mark the beginning and end of the regular expression
The , matches the comma
The \s means whitespace characters (space, tab, etc) and the * means 0 or more
The $ at the end signifies the end of the string

How can I remove the last comma from a string in Perl

Try this

$value =~ s/,\s*$//;

The pattern ,\s*$ matches a comma (,) followed by zero or more space-chars (\s*), followed by the end of the line/input ($).

How to remove the last comma from each line in a string?

This is not too good in terms of performance if your string is very long, but it should do

"\n".join(x[:-1] for x in output.splitlines())

Remove multiple commas from start and end of string

You could match the part between the commas:

const re = /^,*(.*?),*$/;const data = ',,,^^ranbir$$this is first comment,,';const result = data.match(re);
console.log(result[1]);

Remove the last comma in a string

Use a regular expression? Assuming your data frame is DF:

DF$state <- gsub(",$", "", DF$state)

The regular expression ,$ means every comma that occurs at the end of a string. The command gsub replaces every instance of the first argument with the second argument (in this case, nothing) that occurs in the third argument (DF$state).

how to remove comma if string having comma at end

You could try a regular expression:

names = names.replaceAll(",$", "");

Or a simple substring:

if (names.endsWith(",")) {
  names = names.substring(0, names.length() - 1);
}

How can I remove last comma and all spaces from string, then sanitize it using PHP?

Replace spaces and trim commas and spaces at beginning or end:

$result = str_replace(' ', '', trim($string, ', '));

Or:

$result = trim(str_replace(' ', '', $string), ',');

Then if you only want numbers and commas (no letters etc.) maybe:

if(!preg_match('/^[\d,]+$/', $string)) {
    //error
}

However this will not error on a single number with no commas.

How to remove last comma from print(string, end=“, ”)

You could build a list of strings in your for loop and print afterword using join:

strings = []

for ...:
   # some work to generate string
   strings.append(sting)

print(', '.join(strings))

alternatively, if your something has a well-defined length (i.e you can len(something)), you can select the string terminator differently in the end case:

for i, x in enumerate(something):
   #some operation to generate string

   if i < len(something) - 1:
      print(string, end=', ')
   else:
      print(string)

UPDATE based on real example code:

Taking this piece of your code:

value = input("")
string = ""
for unit_value in value.split(", "):
    if unit_value.split(' ', 1)[0] == "negative":
        neg_value = unit_value.split(' ', 1)[1]
        string = "-" + str(challenge1(neg_value.lower()))
    else:
        string = str(challenge1(unit_value.lower()))

    print(string, end=", ")

and following the first suggestion above, I get:

value = input("")
string = ""
strings = []
for unit_value in value.split(", "):
    if unit_value.split(' ', 1)[0] == "negative":
        neg_value = unit_value.split(' ', 1)[1]
        string = "-" + str(challenge1(neg_value.lower()))
    else:
        string = str(challenge1(unit_value.lower()))

    strings.append(string)

print(', '.join(strings))