Cirrus
Cirrus is a word cloud that visualizes the top frequency words of a corpus or document.
Use it with a Jane Austen corpus or with your own corpus.
Overview
The word cloud positions the words such that the terms that occur the most frequently are positioned centrally and are sized the largest. As the algorithm goes through the list and continues to attempt to draw words as close as possible to the center of the visualization it will also include small words within spaces left by larger words that do not fit together snugly. It's important to understand that the colour of words and their absolute position are not significant (if you resize the window or reload the page, words may appear in a different location).
Clicking on words in Cirrus will usually cause one or more other tools to react (if you're in a multi-tool Skins. Hovering over a word will cause a box to appear that displays the frequency count for that term.
Options
Cirrus has a slider near the bottom (with the label "Terms") that allows you to adjust the number of words displayed. The default value is 50.
Clicking on the options icon also allows produces a dialog box with additional settings that can be modified.
- Stopwords: you can define a set of stopwords to exclude – see the Stopwords for more information
- White List: you can define a set of allowed words (the opposite of a stopwords list), only terms in this list will be shown in Cirrus (note that the stopwords list is still active, so you may want to choose "None" from the stopwords menu to deactivate it)
- Font Family: you can determine which font is used by Cirrus, a set of web safe fonts is provided, as well as Lato; you can also specify a font installed on your computer, but of course it may not be available on other computers (in which case a default font is used)
- Palette: you can Palette
Flexible Scale
By default Cirrus shows the top frequency terms for the entire corpus. It's also possible to show top frequency terms for a single document. In the default skin, click on the Documents tab in the lower left side and click on one of the documents – this should cause Cirrus to refresh with words from only the selected document. If you wish to return to the corpus view, click the reset button that appears in the lower right of the Cirrus pane.
Spyral
To use Cirrus in Spyral you can use the following code as a starting point. Modify the config object to modify the visualization.
let config = {
background: null, // set the background colour of the word cloud
categories: null, // set the categories for the word cloud (usually an ID of an existing categories definition)
docIndex: null, // document index to restrict to (can be comma-separated list)
fontFamily: null, // the default font to use for the words (default: "Palatino Linotype", "Book Antiqua", Palatino, serif),
inlineData: null, // user-defined data, most easily expressed like this: love:20,like:15,dear:10
limit: null, // the number of terms to load (that are available, see also visible which determines how many are displayed),
stopList: null, // a named stopword list or comma-separated list of words
visible: null, // the number of terms to display in the word cloud (default is 50)
whiteList: null, // a keyword list – terms will be limited to this list
};
loadCorpus("austen").tool("cirrus", config);Please see Tools.Cirrus for more information about configuration.
Additional Information
The current implementation of Cirrus uses Jason Davies' D3-based Word Cloud library.
Word clouds can be effective at very quickly drawing attention to high frequency terms. They have also been harshly criticized as being highly reductive and even misleading, as argued persuasively by Jacob Harris and others. However, the reduction of information can also be powerful (as in the example of comparing stereotyped vocabulary from advertizing for toys), and Cirrus is perhaps best used in conjunction with other more exploratory and nuanced tools.