Example usage

The workflow

Start by creating a new flow and import the bundled example data called cardata.csv using Datasource and Table.

../../../../_images/datasource_select.png

Use Select rows in Table to keep samples below year 2012.

../../../../_images/select_rows_in_table_flow_2012.png ../../../../_images/select_rows_2012.png

Convert the resulting table into a list of tables using Table to Tables. Add a Report Template Tables and open its configuration dialog.

../../../../_images/add_report_template_tables.png

Creating a scatter plot

Drag a page icon from the items toolbar into the tree view area. Drag a layout item and drop it onto the new page followed by a graph item onto the layout item. An empty graph area should appear in the preview. Now drag a scatter plot and drop it on the Layers node inside the Graph. Expand the Layers node and the scatter plot and click on Dimension 1. Set its data source to cardata.year. For Dimension 2, set the data source to cardata.price. Now a scatter plot with content should be visible in the preview.

../../../../_images/create_scatter.png

Using scales

Create a new scale by opening the Scales page on the left side of the screen. Add a new scale by clicking the plus button at the top. Set its id to size, set the type to linear and enable Use data extent as domain. Finally, set the range to 50, 500. This scale will be used to set the size of the circles in the scatter plot meaning that the sizes will range from 50 to 500.

../../../../_images/create_size_scale.png

Click on Scatter Plot (scatter) in the tree view. In the properies view, enable the checkbox to the right of Size and choose cardata.price as data source and size as scale. The size of the points should now vary by price.

../../../../_images/bind_price_size.png

Now let’s color the circles by year. Start by creating a scale with id color. Use a linear type and set the domain to 1990, 1995, 2000, 2010 and the range to #000000, #0000ff, #ff0000, #ffff00. This means that for input values of 1990 or less we will get a black color. Between 1990 and 1995 the color is linearly interpolated between black and blue, 1995 to 2000 goes between blue and red and finally 2000 to 2010 makes a transition between red and yellow. Interpolation is done in the RGB color space.

../../../../_images/create_color_scale.png

Click on Scatter Plot (scatter) in the tree view and enable the checkbox to the right of Face Color. In the dialog, choose cardata.year as data source and color as scale. The points are now colored by year.

../../../../_images/bind_year_color.png