This is a PHP issue:

$a = 31975454.54545400;
$b = 3197545.45454540;

echo $a+$b;

// Outputs: 35172999.999999

What is the value of precision in your php.ini file?
Increase it and see what happens.

Increasing it from 14 to 17 in PHP 5.3.3 on 32 bit XAMPP:

$a = 31975454.54545400;
$b = 3197545.45454540;

echo $a+$b;

// Outputs 35172999.999999397

This might do the job.

In the code, it can be dynamically set as well:

ini_set('precision', 17);

Our Home Currency is IDR, and we only make transactions with IDR currency only. so we do not need any other currency exchange rates
I have explained in first post, if the quantity order 1 unit then Amount Total is correct, but  for quantity above 2 units make Amount Total wrong.

The easiest way is for you to use the companys' default base home currency as IDR and work from there using standard 8 decimal places for exchange rates and 2 decimals for prices/amounts.

You can play around with the constant FLOAT_COMP_DELTA defined in current_user.inc which is by default set at 0.004. Checkout the function round2() and number_format2() on the use of the value +/- .0000000001 in the same file.

Also see if you can use a larger unit for items to get meaningful rates per unit.

Try 8 decimal places for Exchange Rates and 0 or 2 decimal places for Prices/Amounts.

Any other solution?

thanks

sorry for late reply, current vps server is using:
httpd-2.4.6-45.el7.centos.4.x86_64
mariadb-5.5.52-1.el7.x86_64
on centos 7, this problem is that will very likely to happen, as vendor do include tax in their price, sometimes don't
so the calc will cause floating point decimal.

pls advice. already tested in the latest FA 2.4.2

thanks

Try on a 64 bit machine.
Provide details of PHP version number and Apache/mySQL/OS versions.

Please help solution for this problem?

FrontAccounting ver 2.4.2

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