6.11.3 Polar Crop


This tutorial will demonstrate how to create a cropped polar graph:

Polar Crop Summary.png

Minimum Origin Version Required: 2015 SR0

What You Will Learn

This tutorial will show you how to:

  • Customize the axes settings for a polar graph
  • Crop the graph to show only a portion of the data

Steps to Create the Polar Graph and Customize the Axes

This tutorial is associated with the Tutorial Data project:<Origin EXE Folder>\Samples\Tutorial Data.opj.
You can refer to this graph in Learning Center. (Select Help: Learning Center menu or press F11 key , and then open Graph Sample: Polar Graphs)

  1. Open the Tutorial Data project, and browse to the folder Polar Crop in Project Explorer. Open the workbook Book1AK.
  2. Highlight all the columns and choose Plot > Specialized: Polar theta(X)r(Y) from the main menu to create a polar graph:
    Polar Crop Steps1.png
  3. Custom the Angular Axes
    • The data is difficult to interpret since the range is too small to be adequately represented in a 360 degree plot (Origin sets units to degrees by default). Double-click on the axis to open the Axis Dialog. Go to Scale tab and choose Angular in the left panel. Expand Units Definition node and select the Units to Radians from the drop down. Change the Value option under Major Ticks to 0.25, Count under Minor Ticks to be 9.
    Polar Crop Steps3.png
    • To change the orientation of the plot, go to Show tab and make sure the Angular - Outer is selected in the left panel. Set Direction to Counter Clock-Wise and the Axis Start at(deg) to 270 as shown below:
    Polar Crop Steps2.png
  4. Custom the Radial Axes scale
    • Go to the Scale node and choose the Radial in the left panel. Change the To value to 5.01 (the 0.01 will show the last tick), the Value option under Major Ticks to 0.5 and the Count option under Minor Ticks to 0.
    Polar Crop Steps4.png
  5. Add a Inner Radial Axis
    • In the Show tab, click on the Add a radial axis button on the top of the left panel. Then the Radial - Inner Axis 1 is added in the left panel.
    • To change the orientation of the new inner axis from vertical to horizontal, under Axis Position section, set the Reference as Clock Dial and the Clocks option as 3 O'Clock. Select the Negative radio button to shift the tick labels to the opposite side of the axis:
    Polar Crop Steps5.png
    • To add tick labels on Inner Axis 1, go to Tick Label tab, under Display subtab and select Tick-indexed string from the Type drop-down. Type 0A " " Lv1 " " Lv2 " " Lv3 " " Lv4 in the Display edit box (Spaces within the double quotation marks are to indicate no text label at this tick, so that only every second tick is labelled). Set the Formatting options as shown below:
    Polar Crop Steps6.png
    • Go to the Format subtab and change the tick label format as below:
    Polar Crop Steps6b.png
    • Go to Special Ticks set Axis Begin and Axis End to Hide. Click OK to close the dialog and these settings should create an axis as shown below:
    Polar Crop Steps7.png
  6. Custom the position of Outer Radial Axes
    • Double click on the axis to bring up Axis dialog again. Go to Show tab, and select Radial - Outer 1 in the left panel. Set % of Radius to -46.
    Polar Crop Steps8.png
    • Go Special Ticks tab, set the Axis Begin option to Hide for Radial - Outer 1axis.
    Polar Crop Steps8b.png
    • Repeat the above two steps for Radial - Outer 2 and click OK to exit the dialog box.

Steps to Crop the Polar Graph

The crop tool allows you to magnify and emphasize any particular section of the polar plot.

  1. Double click on any axis to open the Axis Dialog again. Click on the Crop... button to open the Miscellaneous dialog. Check the Enable box and set the values shown in the image below. Click OK to exit the dialog box.
    Polar Crop Steps9.png
  2. The graph will now appear as shown below:
    Polar Crop Steps10.png
  3. In order to change the layer size to match the sample project select Format: Layer from the main menu to open the Plot Details dialog. In the Size/Speed tab, set the following values:
    Polar Crop Steps11.png
  4. Expand Layer1 and select the first data set. Use the Plot Type drop-down on the bottom left of the dialog to change the plot to scatter. Customize the symbol shape and color to resemble the final image (symbol color = Navy, symbol shape = filled circle, error bar color = red).
  5. To remove the negative error bars as in the sample, select the second dataset under Layer1. In the Error Bar tab on the right, clear the Minus box as shown below. The error bar color and thickness can also be adjusted here. OK to exit the dialog box.
    Polar Crop Steps12.png
  6. The final graph should appear as shown below. Delete any unwanted legends and the axis title by selecting them and pressing the Delete key:
    Polar Crop Summary.png