Round a decimal number

[mjocasio23]

I having a problem rounding a number to a certain precision ....

I gettting a value as a string from a form field , then I convert that number to a foat and then applied the round function.... but it does not work as I want it...

var temp   = parseFloat(g_form.getValue('substance_allowance'));

temp = Math.round(temp).toFixed(2); it wont work to rund the value two decimals places if a situation applies.... what it does           it rounds up but it moves the decimals two places to the right.

[Greg42]

Hi Michael,

Try this:

function round (value, digits){

    return (Math.round((value*Math.pow(10,digits)).toFixed(digits-1))/Math.pow(10,digits)).toFixed(digits);

}

You can pass a number or a string and provide a number of digits you want to round your result to.

Regards

Greg

[mjocasio23]

This what I get when I feed with 150.256897 = 1.5026 inconsistent with documentation.

[Greg42]

Hi Michael,

Not sure why you have such results. How do you call the function?

Tests/results:

round(150.256897, 6) / "150.256897"

round(150.256897, 5) / "150.25690"

round(150.256897, 4) / "150.2569"

round(150.256897, 3) / "150.257"

round(150.256897, 2) / "150.26"

round(150.256897, 1) / "150.3"

Looks pretty consistent to me.

Regards

Greg

[mjocasio23]

The only way I got this working was with a converting the value to exponential number...ok I was using round().toFixed(2)...... I did not know the round command contains a second parameter for the decimal places.....

thanks