Polynom - Fitting

[Joachim082]

Hi,

I want to implement a polynomal function 5th order. I have build a trend line in excel which outputs the correct polynomal formula. (table.jpg)

1. option: who can I implement this formula in labview? (polynom.jpg)

2. option: what is wrong with my current labview code? (code.jpg)

Any hints?

Best Regards,

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Joachim

[altenbach]

Get the "linear ramp" from the "signal processing...signal generation" palette, pick the desired start, end, and # of points, and wire to the polynomial evaluation (where you currently have the broken wire).

Graph the output together with the original data on a xy graph.

Instead of three pictures, you could have simply attached your VI with typical data as default. It is much easier to show the problem and solution this way.

[Joachim082 · Accepted solution]

altenbach,

thanks for your response. The scaling of my values aren't linear.

I've attached the example with the solution - I have to work the the polynomial coefficient instead of the best polynomal fit.

Best Regards,

--
Joachim

[altenbach]

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@Joachim082 wrote:

The scaling of my values aren't linear.

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I never said they are linear, but if you want to draw a trendline, it makes sense to do a linear x ramp to calculate the polynomial at each point. I thought you wanted to graph a smooth trend line, e.g. as follows.