Replace everything but number and >actual< decimal points - regex

I'm trying to get a regex working that will replace everything except for numbers and a decimal point (easy). The tricky part: the decimal point is optional but, if present, must be trailed by a further number.
So:
.10 => 10
10. => 10
10.- => 10
1.0 => 1.0
I'm not quite sure how to define the "except numbers followed by an optional decimal point but mandatory number after the optional decimal point" bit :)
Thanks!

It would be something like this:
\d+(\.\d+)?
(Please note that the regex syntax you are using may require different escaping.)

Related

Regex to accept only numeric input with whole and half decimal point

I have used the below regex but it accept all values after decimal point. I want only whole numbers ( eg: 12) and half decimal point (eg 12.5)
Regex regex = new Regex("[^0-9.]+");
I want the below behavior.
For example
Valid numbers : 12, 12.5
Invalid numbers 12.1, 12.8
Try using this pattern:
\d+(?:\.5)?
This would match whole numbers, as well as numbers which half just a decimal component of 0.5. If you also want to allow for 0.0 decimal endings, then use:
\d+(?:\.[05])?
For your actual code, you may use:
Regex regex = new Regex("#\d+(?:\.5)?");

Regex for price, requiring decimal point and 2 decimal places

I am trying to validate a price field in Javascript.
The value can only be numbers, must have 1 decimal point, and must have 2 decimal places after it. Only 7 digits can be in front of the decimal point. Like: 1000000.00
Accepted:
123.00
1.01
0.01
4576.23
1234567.00
1.00
Not accepted:
0.00 (Cannot be free)
0.1 (not 2 decimal places)
1.0 (not 2 decimal places)
01.01 (Cannot start with 0)
12345678.00 (too many digits)
123 (no decimal point and 2 places)
-123.12 (negative, and unacceptable character)
123.123 (too many places)
I am unsure how to approach this problem and any help would be appreciated. A simple guide on how to do write my own regex would be helpful too as English is not my strong point. Thanks in advance.
Here's what I tried on my own: /^[0-9]+.[0-9]{2}$/
But I am unsure how to approach the 0 and length problem.
This regular expression will solve your problem. I have checked it against all the options you have given in question.
^(0(?!\.00)|[1-9]\d{0,6})\.\d{2}$
If you don't know how to test a regular expression against a string in JavaScript you can check below link.
http://www.w3schools.com/jsref/jsref_regexp_test.asp
Try this pattern ^(?!^0\.00$)(([1-9][\d]{0,6})|([0]))\.[\d]{2}$
It excludes 0.00 and negative numbers and any spaces before or after the number (negative cases)
Hope I covered all possibilities
You can check for test cases here
The following regex pattern matches lines with 1 up to 7 digits followed by a "." and 2 more digits excluding those starting with 0 (or a letter)
^[1-9]\d{0,6}\.\d{2}$

Regexp for digit with decimal with maximum value

I have a regexp to check for a decimal with 2 numbers, but I want to check both the integer and the decimal part for their length.
/^\s*-?[1-9]\d*(\.\d{1,2})?\s*$/;
The above code is decimal with length 2 (ex: 12.23) but I want 10 integer value and 2 decimal value (10,2) like,
1234567890.12
Use /^(?![.])\d{0,10}(\.\d{1,2})?$/
It allows 1.23, 1.2 0.2
Invalid values ., 1.
Depending on what you exactly want, you can use:
/^\s*-?(\d{1,10}(\.\d{1,2})?)\s*$/
for input like: 12.23, 3.4, 1234567890.34, 4, 456, etc., or:
/^\s*-?(\d{10}(\.\d{1,2})?)\s*$/
for: 9087654321, 1234567890.1, 1234567890.23 (10 digits, and optional point and one or two digits), or:
/^\s*-?(\d{10}\.\d{2})\s*$/
for exactly 10 digits fallowed by point and 2 digits, like: 9087654321.12, etc. Its all depends on what kind of numbers you want to filter.

CLR Regex for fractions

I need a CLR Regex for fractions or whole numbers and fractions where
1/2 is correct
12 2/3 is correct too
and a minus sign can popup just before any number.
I first came up with -?([0-9]* )?-?[0-9]+\/-?[0-9]+ but that seems to allow 2/7 12 too for example.
Well, that regex would be in two parts, the (optional) whole number:
(:?-?\d+ )?
and the fractional part:
-?\d+/-?\d+
And we need to match the complete string; so:
^(:?-?\d+ )?-?\d+/-?\d+$
Testing a bit:
PS> $re=[regex]'^(:?-?\d+ )?-?\d+/-?\d+$'
PS> "1/2","12 1/2","-12 2/3","-5/8","5/-8"|%{$_ -match $re} | gu
True
However, this allows for "-12 -2/-3" as well, or things like "1 -1/2" which don't make much sense.
ETA: Your original regex works, too. It just lacked the anchors for begin and end of the string (^ and $, respectively). Adding those make it work correctly.
I just had a similar requirement, but I wanted to match decimal numbers as well.
I came up with the following regex
^-?(?<WholeNumber>\d+)(?<Partial>(\.(?<Decimal>\d+))|(/(?<Denomiator>\d+))|(\s(?<Fraction>\d+/\d+)))?$
Or just this if you don't want named groups
^-?\d+((\.\d+)|(/\d+)|(\s\d+/\d+))?$
To remove the decimal number from validating, it would be shortened to
^-?\d+((/\d+)|(\s\d+/\d+))?$
Hope this helps someone!
try this , just for single fraction and not the whole number
/^\d{1}\/?\d{1}$/

Regular expression accept custom numbers

I need a help
How to change this regular expression that allows to accept positive numbers
like 0, 0.00, .02,etc.. ,
Now this accept 5 digits decimal that is greater than 0 and up to 100
"^100|(\d\d?)(\.(1[01]?|0\d?))?$"
First you should wrap the whole expression except the string boundaries in a group. Otherwise your expression would just say either start with … or end with … as the | has a higher precedence than ^ and $:
^(100|(\d\d?)(\.(1[01]?|0\d?))?)$
And now a solution to your question:
^((100|[1-9]?[0-9])(\.\d{1,2})?|\.\d{1,2})$
I am not sure in which language you are wishing to get the result but it seems quite simple.
The rules are input should start with either digit(s) or decimal point and then, either decimal point or digit(s).