calculate non linear equation lines using excel
 

how do i calcualte a non linear line equation using excel? i have the graph
with the non loinear line on i just need to put the equation on.

Dawn wrote:
how do i calcualte a non linear line equation using excel? i have the graph
with the non loinear line on i just need to put the equation on.


There are hundreds (or thousands) of forms of non-linear equations. You
gotta know what you want to figure out how to get there.

If you're looking for a simple approximation, then for example you can
put your data points onto a chart in Excel. Then right click on the
line on the chart and select "Add Trendline". From that panel choose
the form of non-linear equation you're looking for and on the Options
tab select the "Display Equation on chart".

If you're looking for an exact fit to your data, then you'll need to
know more about mathematics.

Good luck...

Bill

If you have a polynomial fit see my webpage
www.stfx.ca/people/bliengme/ExcelTips on the use of LINEST

If your fit is something else, please reply and we can show how to use
LINEST in many circumstances

best wishes

--
Bernard V Liengme
www.stfx.ca/people/bliengme
remove caps from email

"Dawn" wrote in message
...
how do i calcualte a non linear line equation using excel? i have the
graph
with the non loinear line on i just need to put the equation on.

If the line was put on using Chart|Add Trendline, click on the Options
tab in the Add Trendline dialog and request the "Display equation on chart"

If by "linear line equastion" you mean a simple straight line, look at
help for the SLOPE() and INTERCEPT() functions.

If by "linear line equastion" you mean a model that is linear in the
unkown parameters (polynomials, multiple linear regression, etc) then
use LINEST. Help for LINEST misleads most people into thinking it can
only fit a simple straight line; just pass the array of all X columns.
Bernard Liengme gave a link to his site showing how to do polynomials
with LINEST without having to create a column for each power of x.

Jerry

Dawn wrote:

how do i calcualte a non linear line equation using excel? i have the graph
with the non loinear line on i just need to put the equation on.