Plot Page - Polar Rose Chart

The rose diagram plot properties Plot page contains the options to change the data file; set the bin size; set the error width; and set bar properties. To view and edit rose diagram plot properties, click on the rose diagram plot in the plot window or Object Manager to select it. Then, click on the Plot tab in the Property Manager.

The rose diagram options are edited in the

Property Manager on the Plot tab.

Plot Type

The Plot type property displays the type of plot.

Worksheet

Click the existing data file path and file name next to Worksheet to select a different data file for the plot. Click on a currently open worksheet or click the Browse option to navigate to a worksheet that is not yet open. Select a different data file in the Open Worksheet dialog, and click the Open button to change the data. The plot automatically updates.

NOTE: The worksheet columns are retained after changing the worksheet. If any of the column options are blank after changing the Worksheet, click on the blank option and select the desired column. A blank next to column means that the column does not exist in the new worksheet.

Select the Data in rows option if your data file is formatted where each row includes one variable. When the Data in rows option is selected, all plot properties that require data values are specified by selecting a data row. This includes variables such as X and Y, data labels, worksheet ranges, etc. Properties that list column letters will update to list row numbers. When switching from plotting data in columns to plotting data in rows, Grapher may not be able to select the correct rows automatically. Verify the correct rows are selected.

The property descriptions below refer to data columns, but when Data in rows is selected the property lists will include rows.

Data

Click on the column name next to the Data variable field to change the columns used to create the plot. In the list that appears, select the new column. If the first worksheet row contains header information, the header information appears next to the column letter.

Bar Width

The Bar width controls the range of angle values contained in each bar in the rose diagram, i.e. the automatic bin size. The Bar width is shown in degrees. The Bar width is not available when the Bins type is set to Custom bins.

The first automatic bin always includes zero. Each additional bin begins at slightly greater than the next bin value, which is calculated by adding the zero and the Bar width. All bins include the maximum value for that bin. The exception is the last bin. The last bin is slightly greater than the minimum value and slightly less than 360. 360 is calculated as zero in the automatic bins.

For example, if the Bar width is 10, the first bin includes the values 0 and 10. The next bin would include any values greater than 10 and less than or equal to 20. The third bin would include any values greater than 20 and less than or equal to 30. The last bin would include any values greater than 350 and less than 360.

Bins Type

Rose diagram bins can be automatic or custom. Automatic bins use the value in the Bar width property to determine the bin size of each bar. To change the Bar width bins type, click on the current option and select the desired option from the list.

Setting the Bar width bins type to Automatic bins results in adjacent bars that cover all the data in the polar circle. Setting the Bar width bins type to Custom bins, allows the user to set the minimum and maximum value for each bin individually. To create custom bins, change the Bar width bins type to Custom bins. Click Edit in the Bar width bins field to set the custom values.

Custom Bins

To set the bin ranges individually select Custom bins from the Bar width bins type list and then click Edit next to Bar width bins to open the Custom Bins dialog.

Error

The Error (+/-) field plots an arc with a width that is twice the specified Error (+/-) value. This allows you to set an error bar around the data that has been plotted. This is especially useful when plotting single points with an error distribution. For example, if 5 degrees is the error estimate, error bars that are 10 degrees wide are created and centered over each of the bars. The Error (+/-) property is not available when the Bins type is set to Custom bins.

Click the next to the Error line properties on the Line page to open the error bar line properties section. The line Style, Color, Opacity, and Width can be changed. Click the next to the Error fill style on the Fill page to open the error bar fill properties section. The fill Pattern, Foreground color, Foreground opacity, Background color, Background opacity, Scale, and Stretch can be changed.

Direction

The Direction option sets how rose diagram bars are drawn. If Unidirectional is selected, the data is plotted only in the one direction specified in the worksheet. Selecting Bidirectional creates a mirror image of the data so the data is plotted in two directions. To calculate where the data is plotted using Bidirectional, add 180 degrees to the data value. As an example, if you have a bin size of 45 degrees and it starts at 0, there is a bin at 0-45 degrees and another bin mirrored at 180-225 degrees. To change the Direction, click on the current option and select the new option from the list.

Clipping on Polar Rose Chart

Rose charts are either clipped or not clipped based on the Data Limits Clip to polar circle property.