derivative function

[PETER_AUT]

My program has a derivative calculation. I want to calculate the 2nd derivative of my X,Y-dates. My XY-dates describe a curve, like the graphic in the attachement!

But i am not sure about the assignement from the ports! Is the assignement from the ports right??

Best regards,

PETER

Message Edited by Steirer on 07-29-2005 09:05 AM

Message Edited by Steirer on 07-29-2005 09:06 AM

[GerdW]

Hello Peter,

to get the 2nd derivative you have to call the "Derivative.vi" two times. The parameter you wired with "2" is the sampling period (kind of accuracy). Have a look at the help window!
Perhaps you can include some example values in your X/Y-array as default values?

Message Edited by GerdW on 07-29-2005 09:46 AM

[PETER_AUT]

HI!

I tried to type in some example values, but when i start the program, each array-element has the same value. Because of that, i wall write in this topic some example values!

There is an example: X - Array (10, 19,32,45,51,67,76,81,99)

                                   Y- Array ( 0,2 / 0,191 / 0,17 / 0,16 / 0,13 / 0,16 / 0,18 / 0,19 / 0,199)

The example values should descrive a curve, like the picture above (in my first post )!

I tried to run the program, but the result is only "inf" or "NaN".

What is wrong???

Best regards,

Peter

Message Edited by Steirer on 07-29-2005 10:20 AM

[GerdW]

Hello Peter,

when I use your values I get no inf nor NaN...

See attached example (I only scaled y-values by 1000 for easier typing 🙂

[PETER_AUT]

HI GerdW!

Thank you for your help!

Best regards,

PETER