Difference, Cumulative, Normalize

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 The Difference, Cumulative, Normalize option in the Data menu or the main toolbar can difference the data with adjustable order and lag, compute various cumulatives, and normalize for unit area, unit power, unit standard deviation, and zero mean.

 This option presents a TableCurve 2D graph displaying the input and detrended data.

 Process

 The procedure can generate normalized Data. The Difference item specifies that differencing, the discrete analog of differentiation, is to take place. The Cumulative option specifies that a cumulative, the discrete analog of integration, will be generated.

 Diff. Options

 The difference options are only available if Difference is checked. The Order field specifies the order of the differencing. Most often first order differencing is used. This is the equivalent of taking the first derivative of continuous data. Orders through 4 are supported. The Lag field specifies the delta of the differencing. Usually a lag 1 is used to produce the difference from adjacent elements. A lag of 12 is used sometimes to seasonally adjust monthly data. Similarly, a lag of 4 can be used to seasonally adjust quarterly data.

 If dY is selected, the differencing is based only on the Y-values in the data set. If dY/dX is selected, the differencing is processed like a derivative generating a discrete rate value.

 Cum. Options

 The cumulative options are only available if Cumulative is checked. The Simple option generates a cumulative by basic addition. The Area option uses the x-spacing to produce an area cumulative. The Power option uses the x-spacing to produce a TISA (time-integral squared amplitude) cumulative power data series. For oscillatory data, the cumulative power curve will be continuously increasing.

 Normalize

 The normalizations apply to all processing options. No normalization is made if None is checked. The data can be normalized to Unit Area, Unit Power (TISA), or Unit SD (standard deviation). If the Zero Mean box is also checked, the mean of the resulting series will be zero.

 Data Count

 If differencing is done, the output data count will be reduced. The input and output counts are displayed in the nIn and nOut informational fields.

 List

  The List Data option lists the index, x-values, and the processed data. The listing uses the TableCurve 2D text viewer facility.

 Copy

  The Copy Data to Clipboard option copies the x values and processed data to the clipboard. Formats include full precision binary (for spreadsheets such as Excel) and ASCII (for pasting into text editors).

 Save

  The Save Data to Disk option writes the x-values and processed data to a supported file format. These formats include ASCII, Excel, SPSS, or Systat.

 Production Facility

The Automation facility allows unattended processing of large numbers of data sets. The data sets can come from a text/CSV file or an Excel workbook. The graphs can be exported to an RTF file or streamed to Microsoft Word, while the processed data can be exported to an Excel (xlsx) workbook.

The Reset button restores the data to its state when first entering the procedure.

 MS Word/RTF Export

  The MS Word/RTF File Export option is used to save the current graph to either a MS Word file or a portable RTF (Rich Text Format) file. The graph is inserted into the file as a Windows metafile.

 Updating the Data Table

  When exiting this procedure with the OK button, an option will be presented to update TableCurve 2D's main data table with the processed data.