floating point arithmetics (, or .)

sweahe

I've become a little confused, when my server calculates strings like this:
$var1 = "0.5";
$var2 = "0.7";
echo $var1 + $var2;

I sometimes get the answer 0 and sometimes I get the correct 1.2!
When I get 0 I try to change it to this:
$var1 = "0,5";
$var2 = "0,7";
echo $var1 + $var2;

and I get the correct answer 1,2
I've come to the conclusion now that it depends on the setlocale function!
If I set it to: setlocale(LC_ALL, "swedish");
The calculations wants a ,
if set to: setlocale(LC_ALL, "english");
it wants the .

Is this the way it should be!??
When reading the manual:
http://se.php.net/manual/en/language.types.string.php#language.types.string.conversion

It states:
The string will evaluate as a float if it contains any of the characters '.', 'e', or 'E'. Otherwise, it will evaluate as an integer.

sweahe

If this is OK, can I somehow make MySQL to store float numbers with a , (comma) instead of a . (dot)??

..and also can I get Javascript to calculate with the , (comma) too??

/Andreas

Anon

for best practices, you should forget the comma idea and go with float conversion functions in PHP.

$float_val = (float)$old_val;

then to keep the data integrity, store it in a column with the data type as float.

eg.
.....
mynumber float(10,4)
.....

stores the floating number with the max 10 places before the decimal and 4 after.

sweahe

..but I want to have:
setlocale(LC_ALL, "swedish");