Violin Plot (Plotly)

A Violin plot built with the Plotly.js library. This plot is used to visualize multiple plots simultaneously across various categories or group-memberships. The plot displays a traditional boxplot with quartile notations for each group as well as single points for outliers in the data set. It also conveniently displays a histogram of the data distribution. This node also provides real time statistic values when you "hover" over a particular violin, such as mean, median, and more.

The node supports custom CSS styling. You can simply put CSS rules into a single string and set it as a flow variable 'customCSS' in the node configuration dialog. Current KNIME classes are NOT YET supported, so class names will have to be deduced from the view itself. We are hoping to support standard KNIME classes in an upcoming update.

Please note: the Plotly.js KNIME extension is currently in Labs. It is recommended that you handle missing values and normalize your data before using visualization nodes in this extension to improve performance. Please feel free to leave feedback and suggestions on our community forum here .


General options for the KNIME Violin plot with Plotly.

Data Column
Select the column to be initially compared.
'Group-By' Column (*)
If "Display Legend" is enabled, this column will be used to group different visual elements based on their membership in the chosen "Group-By" column in the legend. With the legend enabled and groups chosen, you can then toggle the visibility of visual elements by group through legend interactions.
Plot direction
The direction to plot the chart. Choosing horizontal will display the numeric column along the x-axis, whereas vertical will display the numeric column along the y-axis.
Report on missing values
When enabled this will display a warning whenever there is a missing value present in the data and give a count on how many missing values exist in the data.
Missing values handling
The way in which this view tries to compensate for missing or invalid values. "Skip rows with missing values" will omit the entire row if a single cell is missing. This can affect multiple traces on the chart in some circumstances. "Leave missing" will leave a gap where the missing value exists and draw the chart anyways.

General Plot Options

These options control the initial state of the view.

Title (*)
The chart title.
Numeric axis label (*)
The label for the axis displaying the numeric column.
Grouped axis label (*)
The label for the axis displaying the grouped column values. Choosing "none" for this column will display one "violin" for the entire data set.
Settings for SVG image generation.
Display legend
When checked, the chart's legend is displayed.
Show warnings in view
When checked, the any warnings will be displayed in the view.
Override colors
When checked, the colors provided by the data table will be ignored and the color chosen below for "Data color" will be applied to the plot. If there are no colors provided with the data, the node will use the "Data color" by default, even if this option has not been selected.
Data color
The color of the data on the plot if there are no colors provided with the table (i.e. from the "Color Manager" node) or if "Override colors" has been chosen. This color will not be automatically applied if the data has "Default" colors, it will only be automatically applied if in the absence of ANY colors. You can always apply this color to the data by selecting the "Override colors" option.
Background color
The background color of the plot, including the axes labels, the title and the subtitle.
Data area color
The background color of the data area, within the axes.

Control Options

Use these options to configure the available controls within the view.

Enable view controls
Check to enable controls in the chart.
Show fullscreen button
When checked, a fullscreen option is displayed in the KNIME interactive menu.
Enable tooltip toggle
Check to enable toggling of the tooltip within the view.
Enable feature selection controls
Check to enable drop down menu's allowing you to switch the features displayed on the axes.
Enable text editing
Check to enable the editing of the title and axis labels within the view.
Enable subscribe to selection toggle
Check to enable toggling of selection subscription within view.
Enable subscribe to filter toggle
Check to enable toggling of filter subscription within view.
Enable link to Plotly editor
Check to enable toggling of filter subscription within view.


This KNIME implementation of Plotly is compatible with the other interactive JavaScript views in the KNIME analytics platform. Use these options to control the degree to which this chart interacts with other views.

Display clear selection button
Displays a button to clear current selection if selection is enabled, you are subscribed to selection or "Enable subscribe to selection toggle" is enabled in the Control Options.
Subscribe to selection events
If checked, the view reacts on notifications from other interactive views that the selection has been changed. See also "Publish selection events".
Subscribe to filter events
If checked, the view reacts on notifications from other interactive views that a filter has been created or modified.

Input Ports

Data table to display in an interactive Violin Plot.

Output Ports

SVG image of the Violin chart if that option has been enabled.
Data table containing the input data with an appended boolean column representing which rows were selected in the view.


Interactive View: Violin Plot
The KNIME Violin Plot with Plotly.




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