Checking for positive or negative number

Question

How can we check if the input number is either positive or negative in LiveValidation?

TheVillageIdiot · Accepted Answer · 2009-07-04T14:00:44.753

5

easier way is to multiply the contents with 1 and then compare with 0 for +ve or -ve

try{
   var n=$("#...").val() * 1;
   if(n>=0){
        //...Do stuff for +ve num
   }else{
       ///...Do stuff -ve num
   }       
}catch(e){
  //......
}

REGEX:

 var n=$("#...").val()*1;
 if (n.match(new RegExp(^\d*\.{0,1}\d*$))) {
   // +ve numbers (with decimal point like 2.3)
 } else if(n.match(new RegExp(^-\d*\.{0,1}\d*$))){
   // -ve numbers (with decimal point like -5.34)
 }

edited Jul 04 '09 at 14:00

answered Jul 04 '09 at 08:21

TheVillageIdiot

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regular expression for checking positive number – Nazmul Hasan Jul 04 '09 at 08:40

Artem Barger · Answer 2 · 2009-07-04T08:19:39.403

4

try
{
    if ((new Number( $('#numberInput').val()) < 0)
    {
        // Number is negative
    }
    else
    {
        // Otherwise positive
    }
} catch ( error)
{
    alert( "Not a number!");
}

edited Jul 04 '09 at 08:19

answered Jul 04 '09 at 08:10

Artem Barger

40,769
9
59
81

score -1 · Answer 3 · answered Feb 04 '11 at 06:55

-1

You can also use JavaScript's method eg:

var pos_value = Math.abs(n_val);

Thanks Dev

answered Feb 04 '11 at 06:55

Dev

7
1

1

The question is finding negative number, not converting to positive numner. – prakashstar42 Dec 09 '14 at 09:01

Checking for positive or negative number

3 Answers3