Returns the argument (theta), an angle expressed in radians, such that:
Syntax
IMARGUMENT(inumber)
Inumber is a complex number for which you want the argument .
Remarks
 Use COMPLEX to convert real and imaginary coefficients into a complex number.
 IMARGUMENT is calculated as follows:
where:
and
z = x + yi
Example
The example may be easier to understand if you copy it to a blank worksheet.
How to copy an example
 Create a blank workbook or worksheet.
 Select the example in the Help topic.
Note Do not select the row or column headers.
Selecting an example from Help
 Press CTRL+C.
 In the worksheet, select cell A1, and press CTRL+V.
 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.

A 
B 
Formula 
Description (Result) 
=IMARGUMENT("3+4i") 
Theta argument of 3+4i, in radians (0.927295) 
