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Scaling the data

The scale maps data values to color values. VisIt provides three scaling options: Linear, Log, and Skew. Linear, which is the default, uses a linear mapping of data values to color values. Log scaling is used to map small ranges of data to larger ranges of color. Skew scaling goes one step further by using an exponential function based on a skew factor to adjust the mapping of data to colors. The function used in skew scaling is (s^d - 1) / (s - 1) where s is a skew factor greater than zero and d is a data value that has been mapped to a range from zero to one. The mapping of data to colors is changed by changing the skew factor. A skew factor of one is equivalent to linear scaling but values either larger or smaller than one produce curves that map either the high or low end of the data to a larger color range. To change the skew factor, choose Skew scaling and type a new skew factor into the Skew factor text field.