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Epoch Folding

Working the technology in a such a way reinforces the concept of utilizing data and operating algebraically on a whole set of data. If the teacher chooses to reinforce this concept using the graphing calculator, the procedure and its options are outlined below.

  • First, the data (secs and intensity) from GX301-2 should be uploaded into the teacher's calculator. It can be inputed into the calculator in Lists named as SECS(time) and INT(intensity). See below.

    table of values for secs,int,per1

    Do you want to know how to name lists?

  • Now link the data from the teacher's calculator to all of the student's calculators.

    Do you want to know how to link lists?

  • The teacher may choose to show students how they could plot the data using the graphing calculator. The plot should mimic the graph contained in this lesson. See below.

    plot showing peaks

    Do you want to know how to plot the data entered?

  • Just like we did for the Epoch Folding procedure previously, we will need to guess the correct P, and divide the data up into time bins. See below.

    table of values for per1,per2,per3

    In this case the data were put into 3 lists of data each containing 27 bins of data.

  • We must now algebraically operate on all 3 lists of binned data in order to calculate the folded data. Specifically we must determine the average intensity for each time bin.

    Do you want to know how to algebraically determine the average intensity for each time bin?

  • Once we do that, we have data ready to be plotted and checked for correctness. You must now go to "STAT PLOT" and input correctly a line plot, and time vs. Intensity correctly in the data.

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