ATAN

Returns the arctangent, or inverse tangent, of a number. The arctangent is the angle whose tangent is number. The returned angle is given in radians in the range -pi/2 to pi/2.

Syntax

ATAN (number)

Number     is the tangent of the angle you want.

Remark

To express the arctangent in degrees, multiply the result by 180/PI( ) or use the DEGREES function.

Example

The example may be easier to understand if you copy it to a blank worksheet.

ShowHow to copy an example

  1. Create a blank workbook or worksheet.
  2. Select the example in the Help topic.

 Note   Do not select the row or column headers.

Selecting an example from Help

Selecting an example from Help
  1. Press CTRL+C.
  2. In the worksheet, select cell A1, and press CTRL+V.
  3. To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Formulas tab, in the Formula Auditing group, click the Show Formulas button.
 
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Formula Description (Result)
=ATAN(1) Arctangent of 1 in radians, pi/4 (0.785398)
=ATAN(1)*180/PI() Arctangent of 1 in degrees (45)
=DEGREES(ATAN(1)) Arctangent of 1 in degrees (45)
 
 
Applies to:
Excel 2003