How 1,5 + 1 = 2,5 Not 2

[Shadowfox]

HOW 1,5 + 1 = 2,5 NOT 2
Should I use some special function for PRECISE mathematical calculation?

[marek_mar]

Huh? Call me an idiot but 1,5 (or 3/2) + 1 (or 2/2) is indeed equal to 2,5 (or 5/2) and not 2 (4/2). And thats quite percise.

[Shadowfox]

Dude, I'm sorry if I haven't made myself clear.
I ask PHP to make a calculation for me:

$a = 1,5
$b = 1
$c = $a + $b

in this case $c = 2 which is not 2,5
What I ask you is how to make PHP calculate this precisely and the echo of my $c variable should be 2,5 not 2.

[slushy77]

Hi Shadowfox,

try this

$a= (float) "1.5";
$b = (float) "1";
$c = $b +$a;

[Spookster]

Run this:



<?php

$a = 1,5;
$b = 1;

$c = $a + $b;

echo $c;

?>



You should see 2.5 echoed to the screen. Also post the exact code you are using where you are getting 2.

[dumpfi]

When typing floating point literals use "." instead of ","
<?php

$a = 1.5;
$b = 1;

$c = $a + $b;

echo $c;

?>dumpfi

[Digger3000]

HOW 1,5 + 1 = 2,5 NOT 2
Should I use some special function for PRECISE mathematical calculation?
What are you talking about? What do 1,5 and 2,5 mean?

[gsnedders]

What are you talking about? What do 1,5 and 2,5 mean?
The character used as the decimal point isn't the same everywhere.

[Shadowfox]

Okay Dumpfi, could you provide me with a REGEX expression which changes all "," characters in a file (.txt) with "."

[NancyJ]

you dont need a regex expression, just str_replace() to change all the commas to decimal points.