Linear Interpolation: Given a pair of (x1,y1), (x2,y2) and x3 predict (x3,y3)

[DeucesAx]

(02-14-2014 04:44 PM)Rich Wrote:  I just recently took Thermodynamics and fluid flow 1. For linear interpolations, i assigned this object which is pretty fast for me:


f(x_1,y_1,x_2,x_3,y_3):=y_2 = (((x_2-x_1)*(y_3-y_1))/(x_3-x_1)) + y_1
x_1 = (Value)
y_1 = (Value)
x_2 = (Value)
y_2 = Unknown
x_3 = (Value)
y_3 = (Value)

To use just perform f(1,1,2.5,10,10) and ENTER

The result should be a direct linear interpolation with y_2 = 2.5

I hope this helps.

Though I recommend just using the EES software package, if it is available at your school and you can use it on an exam. It comes preloaded with almost all tabulated values of entropy, enthalpy, specific heat...etc etc.

Thank you, I will check it out. The linear fit as well.