Grapher Used to Produce Statistical Information About Wind

Grapher 3 has added the ability to create rose diagrams! Rose diagrams are often used to show statistical information about wind. Creating a rose diagram that depicts the frequency of wind in a direction simply requires a single row of data listing the wind direction. Place an entry for each occurrence in a given direction. Grapher then counts the number of occurrences in each bin and creates the graph for you. This process is quick and easy.

Sometimes, it is more important to know the speed of the wind in a particular direction instead of the frequency in that direction. This requires creating multiple columns of data. In the example below, there are three rose diagrams combined into a single graph. Each plot is created from a different column of data that lists the wind directions for a range of wind speeds.

The rose diagram above shows wind speed by color and wind direction. This plot was created by overlaying three different rose diagrams on top of each other.

In the example above, the line color for the plots was changed to invisible and the fill pattern was changed to highlight the different speeds. Grid lines were added to the radial axis to make the frequency of the speeds easier to read. Directions were added to the angular plot to show compass direction instead of degrees around the circle. Although not shown in this graph, error bars can be added to the rose diagram to show uncertainty in the diagram. The result is a customized graph showing only what you want it to show. The new rose diagram plot provides a new way of representing statistical data.