withColumnsWhere method

DataFrame withColumnsWhere(
  1. bool predicate(
    1. String
    )
)

A new data frame with only the columns whose names meet predicate.

Example:

print(iris.withHead(3));
print(iris.withHead(3).withColumnsWhere((c) => c.contains("sepal")));


.--.------------.-----------.------------.-----------.--------.
|id|sepal_length|sepal_width|petal_length|petal_width|species |
:--+------------+-----------+------------+-----------+--------:
|1 |5.1         |3.5        |1.4         |0.2        |setosa  |
|2 |4.9         |3.0        |1.4         |0.2        |setosa  |
|3 |4.7         |3.2        |1.3         |0.2        |setosa  |
'--'------------'-----------'------------'-----------'--------'

.------------.-----------.
|sepal_length|sepal_width|
:------------+-----------:
|5.1         |3.5        |
|4.9         |3.0        |
|4.7         |3.2        |
'------------'-----------'

Implementation

DataFrame withColumnsWhere(bool Function(String) predicate) => withColumns(
    [...numericColumns.keys, ...categoricColumns.keys].where(predicate));