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This element is available since 2018.01, in combination with a dataLayer containing a timeSeriesSet element. If this is set to true (false by default) and the grid geometry contains locationSet in the timeSeriesSet contains (poly)-lines, the lines drawn in the spatial display will include directional arrows. If the time series has a positive value for a line, the arrow will point from the start of the line (first point found in the shape file) to the end of the line (second point found in the shape file). If the value is negative, the arrow is inverted. See the figures for examples.
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