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Ensuring a number is in decimal format

Posted: Thu Mar 02, 2006 9:05 am
by hame22
I have a variable $tax_price that I need to ensure is always in a decimal format; 0.00 (2 decimal places)

I have noticed the printf function for display puurposes, is there a function that can be used to ensure a number is placed into a specified decimal format?

thanks in adavnce

Posted: Thu Mar 02, 2006 10:05 am
by Grim...
From the PHP manual for

Code: Select all

round()
To round any number to a given number of significant digits, use log10 to find out its magnitude:

round($n, ceil(0 - log10($n)) + $sigdigits);

Or when you have to display a per-unit price which may work out to be less than a few cents/pence/yen you can use:

// $exp = currency decimal places - 0 for Yen/Won, 2 for most others
$dp = ceil(0 - log10($n)) + $sigdigits;
$display = number_format($amount, ($exp>$dp)?$exp:$dp);

This always displays at least the number of decimal places required by the currency, but more if displaying the unit price with precision requires it - eg: 'English proofreading from $0.0068 per word', 'English beer from $6.80 per pint'.

Posted: Thu Mar 02, 2006 10:58 am
by John Cartwright