#### 7.7.3 Trigonometric Functions

Trigonometric functions take numeric arguments and produce numeric results.

— Function: ARCOS (number)
— Function: ACOS (number)

> Takes the arccosine, in radians, of number. Results in system-missing if number is not between -1 and 1 inclusive. This function is a pspp extension.

— Function: ARSIN (number)
— Function: ASIN (number)

> Takes the arcsine, in radians, of number. Results in system-missing if number is not between -1 and 1 inclusive.

— Function: ARTAN (number)
— Function: ATAN (number)

> Takes the arctangent, in radians, of number.

— Function: COS (angle)

> Takes the cosine of angle which should be in radians.

— Function: SIN (angle)

> Takes the sine of angle which should be in radians.

— Function: TAN (angle)

> Takes the tangent of angle which should be in radians. Results in system-missing at values of angle that are too close to odd multiples of \pi/2. Portability: none.