This function is accessed from within the Data Module and is used to expand time series data files used to drive simulations either forward or backward in time. This function extrapolates all files of the selected data type. When this function is activated, the following dialog appears:
All the files used by the model of the selected data type are listed. There are two options to direct the extrapolation of each file: data frequency and fill method. Data frequency is the temporal spacing between data lines. The data frequency in the dialog is set based on analysis of existing data in the files, but can be changed manually.
There are three options for the values to put in the extrapolated data lines: missing, zero, or typical. Missing puts a missing value flag for all extrapolated values while zero enters zero for all extrapolated values. The Typical option analyzes existing data in each file to determine the average value on each day of the year. For days for which there is no data, interpolation is used to estimate a typical value. The typical values are then applied to all extrapolated data based on the day of the year. Press OK on the dialog to complete the process, which may take several minutes depending on the number and size of the files.