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Fourier Transform

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To find fourier transform, input expression with respect to an independent variable and then tap  ℱt For example input expression 10 + 4.5cos(2T) + 3sin(4T) where T (time) is an independent variable. Tap on  ℱt  , select independent variable as T used in expression. You also need to provide the fundamental time period TP that you want to use for the transform. For that, input start and end time values for T such that (end - start) = TP (Fundamental Time period) Once TP is provided, the fundamental frequency for the transform will be f0=1/TP and the transform will report coefficients of frequencies in integral multiples of f0 (Harmonics) The default value of start is 0 and end is 2pi for input in radians so that TP=2pi and f0=1/(2pi). (Frequency of sin(T)). You can also set the harmonic range to report from the transform. Default harmonic range that is reported is from 0 to 100. Following results are reported from fourier transform. 1) Magnitude frequency plot in exponent form. 2) Magni
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Fast fourier transform on spreadsheet file data

Assuming that you want to find the fast fourier transform (fft) of data in 2nd column in your spreadsheet file. Use  the ✎ option to open the  variable  editor . Then read the spreadsheet file using the "Read Create Spreadsheet..." option. After the file is read by the app, a page is displayed showing the variable names from 'A' to 'Z' where each variable is mapped to a specific column.  By default, variable Y is mapped to 2nd column so we will perform fft on Y variable.  Simply input the expression Y and tap on  ℱt . Case 1 : You do not have a separate column for corresponding time values in spreadsheet. In that case select independent variable as SEQ_NO and provide the value of deltaT (Time interval between two samples in sequence) Case 2:  You have a separate column for corresponding numeric time values in spreadsheet. Assuming the 1st column in spreadsheet has the time values. Since we know that X is mapped to 1st column, select X as independent time varia
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