[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [EnergyPlus_Support] Performance curve for the chiller

On 22 Feb 2005, at 9:10, wing sun lee wrote:

> I have already checked the microsoft office excel, but it can only solve the
> curve fit for linear and quadratic equation by the Linest() function.

There is a trick that was taught to me that allows "Linest" to be used to fit 
higher power equations.  You must first create additional columns which compute 
the higher powers or other forms of the independent variables.  For example, to 
solve a bi-quadratic in Excel:
Col A= X
Col B= X^2
Col C= Y
Col D= Y^2
Col E= X*Y
Col F= Dependent variable

Then tell Linest that columns A:E are the independent variables and col F is 
the dependent variable.  I will try to prepare a sample spreadsheet to post in 
the files area.


Michael J. Witte, GARD Analytics, Inc.
EnergyPlus Testing and Support      

The primary EnergyPlus web site is found at:

The group web site is:

Attachments are not allowed -- please post any files to the appropriate folder in the Files area of the Support Web Site.
Yahoo! Groups Links

<*> To visit your group on the web, go to:

<*> To unsubscribe from this group, send an email to:

<*> Your use of Yahoo! Groups is subject to: