Atan()

atan(<number>[, <units>])

atan2(<number1>, <number2>[, <units>])

Returns the arctangent of <number> or <number1>/<number2>. The range of atan() is always an angle in quadrants 1 and 4. Taking into consideration the sign of <number1> and <number2>, atan2() can return an angle in all four quadrants. The value returned will be expressed in <units>. <units> may be 'radians', 'degrees', or 'gradians' or just the first letter of any of these.

By default, <units> is 'radians'.

In a circle, there are 2*pi() radians, 360 degrees, and 400 gradians.

Example

> say atan(0)

You say, "0"

> say tan(1)

You say, "1.5574077246549023"

> say atan(1.5574077246549023)

You say, "1"

Related Topics

acos(), asin(), cos(), ctu(), pi(), sin(), tan()