is_long

The is_long() function in PHP is simply an alias of is_int() - for full details see the is_int() function.

is_real

The is_real() function in PHP is simply an alias of is_float() - for full details see the is_float() function.

is_numeric

The is_numeric() function allows you to check if a particular variable is a numeric string. Numeric strings can consist of a sign, any number of digits, a decimal part and an exponential part.

PHP

$my_string = '+1.998';
var_dump( is_numeric($string1) );
// => true

Ruby

def is_numeric?(num)
    true if Float(num) rescue false;
end
 
my_string = '+1.985';
puts is_numeric?(my_string);
# => true

is_int

The is_int() function allows you to check if a particular variable is an integer (type).

PHP

$number = 9.5;
var_dump( is_int($number) );
// => false

Ruby

number = 9.5;
puts number.is_a?(Integer);
# => false

is_bool

The is_bool() function allows you to check if a particular variable is a boolean (type).

PHP

$my_variable = 1;
var_dump( is_bool($my_variable) );
// => false

Ruby

 my_variable = 1;
puts my_variable.is_a?(FalseClass) || my_variable.is_a?(TrueClass)
# => false

is_float

The is_float() function allows you to check if a particular variable is a float (type).

PHP

$number = 6.5;
var_dump( is_float($number) );
// => true

Ruby

number = 6.5;
puts number.is_a?(Float);
# => true

array_sum

Returns the sum of values in an array.

PHP

$a = array(2, 4, 6, 8);
echo array_sum($a);
// => 20

Ruby

a_var = [2, 4, 6, 8];
puts a_var.inject {|sum,x| sum ? sum + x : x };
# => 20

In the code above, the return value from the ruby code will be nil if the array used is empty. This is not exactly the same behaviour as PHP, since the array_sum() function will always return a number. We can force ruby to always return a float (or an int) too, even if the array is empty, by adding a bit of type casting to the final result:

Ruby

a_var = [];
puts a_var.inject {|sum,x| sum ? sum + x : x }.to_f;
# => 0.0

pi

Returns the value of PI to 14 (default) decimal places. This precision can be altered in the php.ini file.

PHP

echo pi();
// => 3.1415926535898

Ruby

puts Math::PI;
# => 3.14159265358979

In the code above, PI is actually a constant of the Module Math. PHP also has a constant which stores the approximate value of PI - M_PI.

PHP

echo M_PI();
// => 3.1415926535898

abs

Returns the absolute value for a number.

PHP

echo abs(-4.2);
// => 4.2;

Ruby

puts -4.2.abs;
# => 4.2;

acos

Returns the arc cosine of the argument provided in radians.

PHP

echo acos(0.7);
// => 0.79539883018414;

Ruby

puts Math.acos(0.7);
# => 0.79539883018414;