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matlabmeasurementextrapolation

Extrapolate a set of measurement data with Matlab

There is data given from a csv-File. It contains the resistance of a cooling metal piece at a certain time. The measuremnt started at t=7.8s. The task is to extrapolate the graph from 7.8s to 0s to determine the highest resistance and thus the maximum temperature. How can I acheive this using matlab? I tried the following that did not yield satisfying results.

data = csvread('05A_edit.csv');
time = data(:,2)+7.8;
resistance = data(:,3);
timep = linspace(0,7.8,167);
resistancep = interp1(time,resistance,timep,'linear','extrap');
plot(time,resistance,'b',timep,resistancep,'r');

The plot of the raw data looks the following: enter image description here

Thank you in advance.

Solution

  • I would use fitting. Do you have ideas about your data? It looks exponential. I would use:

    [fitresult, gof]=fit(x,y,'exp1')
Y1=fitresult (X1)