Transform Boxplot

A boxplot transform generates statistics for making a box plot.

Invalid values are filtered out.

Quantile properties

Property Type Description
boxplot string A field to make a boxplot of
extent number | 'min-max' (Optional, default: 1.5) Threshold for outliers. Data values outside of the IQR (Interquartile Range) multipled by extent will be indicated as outliers. If it is min-max then there will be no outlier computed.
groupby Array[String] Nominal fields to group the boxplots by.

Output field names

In addition to the field names specified for boxplot and in groupby, a boxplot transform produces a predetermined field names:

Field Type Description
key string The type of this record: whisker_lower (lower bound), q1 (25% qunatile), median, q3 (75% qunatile), whisker_upper(upper bound), outlier.
role 'point'|'outlier' Whether it is 'outlier' or not ('point').
order number The order of values (in ascending order): lower outliers, lower bound, 25% quantile, median, 75% quantile, and upper outliers.
group_name string Idnetifier for groups.

Usage pattern

JSON

{
  ...
  "transform" : [
    {
      "boxplot": "speed",
      "groupby": [
        "category"
      ]
    },
  ]
  ...
}

JavaScript

let stream = new Erie.Stream();
...
let boxplot = new Erie.Boxplot("speed", 1.5) // field, extent;
boxplot.groupby(["category"]);
stream.transform.add(boxplot);
...
© Hyeok Kim