Trendline and 3-D chart

[sudhanshu]

Hi

I am have a problem wherein on X axis Rel. Humidity is plotted while on
Y axis Power Output is plotted for different ambient temperatures.

I have the data for four ambient temperatures viz. 0, 15, 30 and 45 deg
celsius. The data looks like as below :

Re. Hum. PO@0 C. PO@15 C PO@30C PO@45 C
0 1.0000 1.2 1.4 2
10 1.1000 1.4 1.48 2.2
20 1.2000 1.6 1.56 2.4
30 1.3300 1.8 1.64 2.6
40 1.4600 2 1.72 2.8
50 1.5900 2.2 1.8 3
60 1.7200 2.4 1.88 3.2
70 1.8500 2.6 1.96 3.4
80 1.9800 2.8 2.04 3.6
90 2.1100 3 2.12 3.8
100 2.2400 3.2 2.2 4

I have been able to plot four individual curves with their respective
trendlines and their equations, however, I am unable to find a way out
for obtaining data for an intermediate value of temperature for eg. 32
deg. celsius.

I have two questions to ask:

a) Is there a way to obtain a trendline equation wherein by inputting
two variables viz. ambient temperature and rel. humidity values, Power
Output is directly obtained.

b) Is there any way to link the trendline equation to cell (s) wherein
for already available inputs (like here ambient temp. and rel.humid.)
the output is obtained (for eg. Power Output).

Thanking for your help in advance.
Sudhanshu

 

[Jerry W. Lewis]

Use LINEST. The first paragraph of Help is misleading, LINEST is not
restricted to straight lines, it fits any model that is linear in the
unknowns.

Jerry