Appearance

ACOS function ​

Overview ​

ACOS is a function of the Math and Trigonometry category that calculates the inverse cosine (arccosine) of a number in the range [-1 to 1], returning an angle in the range [0 to π], expressed in radians.

Usage ​

Syntax ​

ACOS(number) => acos

Argument descriptions ​

  • number (number, required). The number whose arccosine is to be calculated, in the range [-1 to 1].

Additional guidance ​

None.

Returned value ​

ACOS returns a number in radians in the range [0 to π] that is the angle whose cosine is the specified number.

Error conditions ​

  • In common with many other IronCalc functions, ACOS propagates errors that are found in its argument.
  • If no argument, or more than one argument, is supplied, then ACOS returns the #ERROR! error.
  • If the value of the number argument is not (or cannot be converted to) a number, then ACOS returns the #VALUE! error.
  • If the value of the number argument lies outside the range [-1 to 1], then ACOS returns the #NUM! error.
  • For some argument values, ACOS may return a #DIV/0! error.
  • For more information about the different types of errors that you may encounter when using IronCalc functions, visit our Error Types page.

Details ​

  • The ACOS function utilizes the acos() method provided by the Rust Standard Library.
  • The figure below illustrates the output of the ACOS function for angles x in the range -1 to +1.

Examples ​

See some examples in IronCalc.