Cloudera Docs

Radial

In Cloudera Data Visualization, Radial charts are a good approach for comparing the relative values of several measures. These measures are assigned an equal angle of rotation, and the relative values are represented through the areas of each wedge.

The following steps demonstrate how to create a new Radial visual representation on the US County Population dataset, for which the data source is samples.us_counties]. For an overview of shelves that specify this visual, see Shelves for radials.

  1. Start a new visual based on the US County Population dataset (data source samples.us_counties).
    For instructions, see Creating a visual.
  2. In the VISUALS menu, find and click Radial.
    The shelves of the visual changed. They are now Dimensions, Measures, Tooltips, X Trellis, Y Trellis, and Filters. Both Dimensions and Measures are mandatory.
  3. Populate the shelves from the available fields (Dimensions and Measures) in the DATA menu.
    1. Under Dimensions, select ctyname, and add it to the Dimensions shelf.
    2. Under Measures, select the following and add them all to the Measures shelf: wa_male, ba_male, ia_male, aa_male, na_male and tom_male.
    Now all fields on the Measures shelf show the sum of male populations.
  4. To show both male and female (total) in the group, change the calculations for the fields: change the expression sum([wa_male] to (sum([wa_male])+sum([wa_female])), and so on.

    The following steps demonstrate how to use the Expression Editor:

    1. On the shelf of the visual, click the (caret-right) icon to the right of the field.
    2. In the FIELD PROPERTIES menu, click [ ] Enter/Edit Expression.
    3. In the Enter-Edit Expression modal window, edit the text manually or pull in the appropriate functions and fields.
    4. Click VALIDATE EXPRESSION to ensure that the computation works, and then click SAVE.
    5. Click the x icon at the top of the FIELD PROPERTIES menu to close it.
    The column in the shelf now appears to hold the expression.
  5. To improve the appearance of the visual, alias ctyname as County on the Dimensions shelf, and all the fields on the Measures shelf according to the following:
    • (sum([wa_male])+sum([wa_female])) as White
    • (sum([ba_male])+sum([ba_female])) as Black or African American
    • (sum([ia_male])+sum([ia_female])) as American Indian and Alaska Native
    • (sum([aa_male])+sum([aa_female])) as Asian
    • (sum([na_male])+sum([na_female])) as Native Hawaiian and Other Pacific Islander
    • (sum([tom_male])+sum([tom_female])) as Two or More Races

    Follow the steps to create an alias:

    1. On the shelf of the visual, click the caret-right icon to the right of the field.
    2. In the FIELD PROPERTIES menu, click the caret-right icon next to Alias.
    3. In the text box below Alias, enter the alias name of column, as it should appear in the visual.
    4. Click the x icon at the top of the FIELD PROPERTIES menu to close it.
    The shelf now shows the column with its alias name.
  6. Click REFRESH VISUAL.
  7. Note all the information provided by the visual, for each county. Also, note how long the visual is, as it lists every county in the nation.
  8. Optional: Filter on the stname field to see a smaller visual, or trellis the visual on the stname field.
    For instructions, see Trellised radial.
  9. Optional: Adjust the axes depending on what your visual demonstrates: comparison of measures within same dimension, relative values of measure compared to same measure across all dimensions, or relative values of measures compared to all measures across all dimensions.
    For instructions, see Changing the axes scale for radial graphs.
  10. Optional: You can replace the default 'wedge' representation of the radial chart with complete circles by enabling the overlap option on the Marks menu.
    For instructions, see Changing display to overlap.
  11. Click the pencil/edit icon next to the title of the visualization to enter a name for the visual.

    In this example, the title is changed to 'Populations, by County - Radial'. You can also add a brief description of the visual as a subtitle below the title of the visualization.

  12. At the top left corner of the Dashboard Designer, click SAVE.