The Excel IMREAL Function

Home » Excel-Built-In-Functions » Excel-Engineering-Functions » Excel-Imreal-Function

Search this site:

Custom Search

Related Function :

IMAGINARY Function

Complex Numbers

Within the world of complex numbers, the 'imaginary' value, i is used to represent the square root of -1.

A Complex Number is composed of a real number combined with an imaginary number.

E.g. The complex number, z, is written as

z = 5 + 2i

Basic Description

The Excel IMREAL function returns the real coefficient of a supplied complex number

- i.e. the function returns the value a, for the complex number a + bi.

The format of the Imreal function is :

IMREAL( Inumber )

where the Inumber argument is a Complex Number.

Note that complex numbers are simply stored as text in Excel. When a text string in the format "a+bi" or "a+bj" is supplied to one of Excel's built-in complex number functions, this is interpreted as a complex number.

Also the complex number functions can accept a simple numeric value, as this is equivalent to a complex number whose imaginary coefficient is equal to 0.

Therefore, the Inumber argument can be supplied to the Excel Imreal function as either:

	-	A simple number
or
	-	A complex number encased in quotation marks - eg. "5+3i"
or
	-	A reference to a cell containing a complex number or a numeric value
or
	-	A value returned from another Excel function or formula

These are all included in the examples below.

Examples

In the example below, the Excel Imreal function is used find the real coefficient of different complex numbers.

The format of the function is shown in the spreadsheet on the left and the results are shown in the spreadsheet on the right.

Formulas

	A	B
1	5+2i	=IMREAL( A1 )
2		=IMREAL( "2+2i" )
3		=IMREAL( 6 )
4		=IMREAL( "3i" )
5		=IMREAL( COMPLEX( 4, 1 ) )

Results

	A	B
1	5+2i	5
2		2
3		6
4		0
5		4

Further information on the Excel Imreal function can be found on the Microsoft Office website.

Common Errors

If you get an error from the Imreal function this is likely to be one of the following :

#NAME?

Occurs when Analysis ToolPak add-in is not enabled in your Excel.
You will need to enable the add-in if you want to use the Excel complex number functions.

To do this in Excel 2003 :

From the Tools drop-down menu, select the option Add-Ins ...
An 'Add-Ins' window will pop up. From this, select the option Analysis ToolPak and click OK

To do this in Excel 2007 :

Click the Microsoft button on the top left of your spreadsheet and select the Excel Options button
From the menu on the left hand side, select Add-Ins
In the 'Manage:' box, select Excel Add-ins and click Go...
An 'Add-Ins' window will pop up. From this, select the option Analysis ToolPak and click OK