HeatMap (JFreeChart)

This node visualizes the input data as a HeatMap. A HeatMap visualizes a matrix by coloring each entry of the matrix with a color scale. For generating the HeatMap a column of type DistanceVector or ListCell has to be selected from the input data. Alternatively, multiple numerical columns can be selected. The minimal value, found in the matrix of numbers, is mapped to the color selected as lower bound and the maximal value to the upper bound. The entries inside the range are assigned a color inside this range. If the value can't be extracted, e.g. a missing value, the corresponding block is transparent.

Options

Select distance or list cell column:: Defines the column that contains the DistanceVectors or ListCell (of numbers). Select none for using multiple numerical columns.
Column selection: Select the numerical columns to be visualized.
Upper bound color: The color to represent the biggest value.
Lower bound color: The color to represent the lowest value.
Show color-scale legend: Adds the color-scale legend for to the chart.
Use all rows: Defines whether all rows in the input table should be used for calculations. If unchecked the maximum number of rows processed can be limited.
No. of rows to display: Use this numerical value to restrict the number of rows included in the visualization.
Show tool tips: If selected tooltips can be seen in the special JFreeChart view (second tab in the view). This is helpful for identifying areas in the plot. However the tooltip generation needs a lot of time and memory, thus this option should be used with care. We can recommend this option until 500 rows (or a 500*500 elements)

Axis configuration

Label for X Axis: If checked the axis label for the plot's domain axis would be defined by the given text.
Label for Y Axis: If checked the axis label for the plot's range axis would be defined by the given text.
Show domain axis: If checked the domain axis is shown on the image together with the tick marks and labels
Domain axis tick labels orientation: Allows user to specify the orientation of the domain axis tick labels.
Show range axis: If checked the range axis is shown on the image together with the tick marks and labels
Range axis tick labels orientation: Allows user to specify the orientation of the range axis tick labels.

General Plot Options

Type of Image: The type of the created image can either be png or svg. PNGs are mostly smaller, SVGs provide details about plot and the possibility to be changed individually.
Title of Graph: The title of the graph shown above the generated image. If the title is not activated, no title will be shown.
Width of Image (in pixel): The width of the generated image, not the plot width.
Height of Image (in pixel): The height of the generated image, not the plot height.
Background Color: The color of the background of the image. Hence this color is used for the area behind and around the plot as well as behind potential axis and legends.
Plot Background Color: The color of the background of the plot. Hence this color is used for the empty space in a plot.
Plot Background Alpha: The transparency of the plot background can be modified using an additional alpha value. An alpha value of 1 does not change the background transparency. Decreasing the alpha value will increase the plot background transparency.
Scale Font Size: Factor changes the font sizes within the JFreeChart view. A value greater the 1 increases all view fonts, a value between 0 and 1 decrease them.

Input Ports

: Data table with at least one column of type DistanceVector or ListCell

Output Ports

: The image of the plot (SVG or PNG)

Popular Predecessors

Popular Successors

Views

Heat Map: Heat Map of the input data.

Workflows

Developers

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