IS THERE AN INTERPOLATION FUNCTION IN EXCEL 2003

[Cooper]

In the past I was able to use an interpolation function that would give me an
interpolated value from a series of numbers. For example, in excel, my 'A'
column would constist of a column of numbers (these numbers would be
different elevations) and my 'B' column would consist of a column of numbers
(these numbers would be areas that were associated with the elevations). If
I used the interpolation function, in a cell I would list an elevation that
was between the known elevations and the cell that contained the function
would calculate the interpolated area for that elevation. However, recently
I just got a new computer that has Excel 2003 and I can not find this
function. If anyone can offer any advice, I would greatly appreciate it.

 

[William Horton]

What is the specific function. It probably was a function that was in one of
Exce's add-in's. Follow the Excel menu path Tools / Add-in's and see if you
can figure out which add-in it was in. Or if you do an on-line or help
search it may tell you what add-in the function is in.

Hope this helps.

Bill Horton

 

[B. R.Ramachandran]

Hi,

It seems to be that the trendline equation for the plot of Area vs Elevation
had been entered as a formula in the spreadsheet to calculate the Area for
any Elevation value.

Obtain the trendline equation for the XY plot of Area (Column B values,
y-range) vs Elevation (Column A values, x-range). You can use that equation
for calculating the Area value for any Elevation value. For example, let's
suppose that the trendline equation for the Area vs Elevation plot is y=1.2
x^3 - 3.8x^2 - 2.1x + 4.8. In a cell in the spreadsheet, say C2, enter the
elevation value for which you want to estimate the area value. In D2 (this
is where the area will be calculated) enter the formula =1.2*D2^3 - 3.8*D2^2
- 2.1*x + 4.8, and clcik ENTER. The formula calculates an interpolated area
value. You can change the number in C2, and D2 would update appropriately.

Regards,
B. R. Ramachandran