XY graph interpolation

[akc]

Hello all,

I am new to Labview. Probably, this is simple question, but I am really stuck on it. I have a XY graph (temp Vs resistance for thermistor; the curve looks like decay fucntion), for each unit degree there is corresponding Resistance but I want to get corresponding resistace for some decimal temp(like 10.5 or 18.1 C) using some kind of interpolation. Any kind of help here. Thanks in advance.

[altenbach]

You did not include the datafile.

[altenbach · Accepted solution]

Try this. (assuming you want linear interpolation).

[akc]

Thanks for reply.

Here is the data file. Sorry, I couldn't upload the CVS(comma delimited file).

[altenbach]

Since your T values are equally spaced and coincide with the array index, you can simplify significantly.

[akc]

Yap thanks for the advice and solution. One more question to bother you. sorry. Now I have to interpoate Resistance vs Temp i.e for a give resistance what is the tempeature. In this case the resistance is not in equal interval. How should I deal with this problem? 

Again thanks

[akc]

And yap I tried by switch the columns from your previous VI and seems like it doesnot work if x-is resistance so as to get y-value (i.e temp). Any suggestions!!!! Thanks.

[altenbach]

You are lucky that the mapping is unique. You can use "threshold array" in the same way, but since you data is decreasing, negate the array and the search value to get the correct result. Check the online help.

[akc]

Thank you for your help. Really appreciated!!