ATAN function

Overview

ATAN is a function of the Math and Trigonometry category that calculates the inverse tangent (arctangent) of a number, returning an angle in the range [-$\pi$/2 to +$\pi$/2], expressed in radians.

Usage

Syntax

ATAN (number) => atan

Argument descriptions

• number (number, required). The number whose arctangent is to be calculated, in the range [-$\mathrm{\infty }$, +$\mathrm{\infty }$].

Additional guidance

None.

Returned value

ATAN returns a number in radians in the range [-$\pi$/2 to +$\pi$/2] that is the angle whose tangent is the specified number.

Error conditions

• In common with many other IronCalc functions, ATAN propagates errors that are found in its argument.
• If no argument, or more than one argument, is supplied, then ATAN returns the #ERROR! error.
• If the value of the number argument is not (or cannot be converted to) a number, then ATAN returns the #VALUE! error.
• For some argument values, ATAN 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 ATAN function utilizes the atan() method provided by the Rust Standard Library.
• The figure below illustrates the output of the ATAN function for angles $x$ in the range [-$\mathrm{\infty }$, +$\mathrm{\infty }$].

Examples

See some examples in IronCalc.

Links

• For more information about inverse trigonometric functions, visit Wikipedia's Inverse trigonometric functions page.
• See also IronCalc's SIN, COS and TAN functions.
• Visit Microsoft Excel's ATAN function page.
• Both Google Sheets and LibreOffice Calc provide versions of the ATAN function.