1. Aritmetic operations
In PHP are 6 simple aritmetic operations. First these are the 4 basic aritmetic operations
+, -, * and / (/
is the division as : is already used in php and / is used
in any other programming language, too), and there is the unary operator -
which negates a number and the operator % which calculate the remains of
a division (20:7 = 2 remaining 6).
<?php
$a = 10;
$b = 6;
echo $a-$b; // 4
echo $a+$b; // 16
echo $a*$b; // 60
echo $a/$b; // float(1.66666666667)
echo -$a; // -10, same as echo 0-$a;
echo $a%$b; // 4 (6 fits one times in 10 with a remain of 4)
?>
For any complex calculaten there exists a lot of functions, to find in the manual
at Mathematical Functions.
Especially pow is such a function which calculates the exponentation.
Beginners try to use ^ as the exponentation and fails as php use
^ for something different than the exponentation (it is used for
a bitwise XOR operation).
<?php
$base = 5;
$exponent = 7;
echo $base^$exponent; // echos 2, which is not what you want
echo pow($base, $exponent); // echos 78125
?>
