PARSEBOOL Function

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Evaluates a String input against the Boolean datatype. If the input matches, the function outputs a Boolean value. Input can be a literal, a column of values, or a function returning String values.

After you have converted your strings values to Booleans, if a sufficient percentage of input strings from a column are successfully converted to the other date type, the column may be retyped.

Wrangle vs. SQL: This function is part of Wrangle, a proprietary data transformation language. Wrangle is not SQL. For more information, see Wrangle Language.

Basic Usage

parsebool(strInput)

Output: Returns the Boolean data type value for strInput String values.

Syntax and Arguments

parseint(str_input)

Argument	Required?	Data Type	Description
str_input	Y	String	Literal, name of a column, or a function returning String values to match

For more information on syntax standards, see Language Documentation Syntax Notes.

str_input

Literal, column name, or function returning String values that are to be evaluated for conversion to Boolean values.

Missing values for this function in the source data result in null values in the output.
Multiple columns and wildcards are not supported.

Usage Notes:

Required?	Data Type	Example Value
Yes	String	'false'

Examples

Tip: For additional examples, see Common Tasks.

Example - type parsing functions

This example shows how to use parsing functions for evaluating input values against the function-specific data type.

Functions:

Item	Description
PARSEBOOL Function	Evaluates a String input against the Boolean datatype. If the input matches, the function outputs a Boolean value. Input can be a literal, a column of values, or a function returning String values.
PARSEDATE Function	Evaluates an input against the default input formats or (if specified) an array of Datetime format strings in their listed order. If the input matches one of the formats, the function outputs a Datetime value.
PARSEFLOAT Function	Evaluates a String input against the Decimal datatype. If the input matches, the function outputs a Decimal value. Input can be a literal, a column of values, or a function returning String values.
PARSEINT Function	Evaluates a String input against the Integer datatype. If the input matches, the function outputs an Integer value. Input can be a literal, a column of values, or a function returning String values.

Source:

The following table contains data on a series of races.

raceId	disqualified	date	racerId	time_sc
1	FALSE	2/1/20	1	24.22
2	f	2/8/20	1	25
3	no	2/8/20	1	24.11
4	n	1-Feb-20	2	26.1
5	TRUE	8-Feb-20	2.2	-25.22
6	t	2/8/2020 10:16:00 AM	2	25.44
7	yes	2/1/20	3	24
8	y	2/8/20	33	29.22
9	0	2/8/20	3	24.78
10	1	1-Feb-20	4	26.2.1
11	FALSE	8-Feb-20		28.22 sec
12	FALSE	2/8/2020 10:16:00 AM	4	27.11

As you can see, this dataset has variation in values (FALSE, f, no, n) and problems with the data.

Transformation:

When the data is first imported, it may be properly typed for each column. To use the parsing functions, these columns should be converted to String data type:

Transformation Name	`Change column data type`
Parameter: Columns	`disqualified,date,racerId,time_sc`
Parameter: New type	`String`

Now, you can parse individual columns.

disqualified column:

Transformation Name	`Edit column with formula`
Parameter: Columns	`disqualified`
Parameter: Formula	`PARSEBOOL($col)`

racerId column:

Transformation Name	`Edit column with formula`
Parameter: Columns	`racerId`
Parameter: Formula	`PARSEINT($col)`

time_sc column:

Transformation Name	`Edit column with formula`
Parameter: Columns	`time_sc`
Parameter: Formula	`PARSEFLOAT($col)`

date column:

For the date column, the PARSEDATE function supports a default set of Datetime formats. Since some of the listed formats are different from these defaults, you must specify all of the formats. These formats are specified as an array of string values as the second argument of the function:

Tip: For the PARSEDATE function, it's useful to use the Preview to verify that all of the dates in the column are represented in the array of output formats. You can see the available output formats through the data type menu at the top of a column in the Transformer Page.

Transformation Name	`Edit column with formula`
Parameter: Columns	`date`
Parameter: Formula	`PARSEDATE($col, ['yyyy-MM-dd','yyyy\/MM\/dd','M\/d\/yyy hh:mm','MMMM d, yyyy','MMM d, yyyy'])`

After all of the date values have been standardized to the output format of the PARSEDATE function, you may choose to remove the time element of the values:

Transformation Name	`Replace text or pattern`
Parameter: Column	`date`
Parameter: Find	` {digit}{2}:{digit}{2}:{digit}{2}{end}`
Parameter: Replace with	`''`

Results:

After executing the above steps, the data appears as follows. Notes on each column's output are below the table.

raceId	disqualified	date	racerId	time_sc
1	false	2020-02-01	1	24.22
2	false	2020-02-08	1	25
3	false	2020-02-08	1	24.11
4	false	2020-02-01	2	26.1
5	true	2020-02-08	null	-25.22
6	true	2020-02-08	2	25.44
7	true	2020-02-01	3	24
8	true	2020-02-08	33	29.22
9	false	2020-02-08	3	24.78
10	true	2020-02-01	4	null
11	false	2020-02-08	null	null
12	false	2020-02-08	4	27.11

disqualified column:

The PARSEBOOL function normalizes all valid Boolean values to either false or true.

racerId column:

The PARSEINT function writes invalid values as null values.
The function writes empty values as null values.
The value 33 remains, since it is a valid Integer. This value should be fixed manually.

time_sc:

The PARSEFLOAT function writes the source value 25.00 as 25 in output.
The source value -25.22 remains. However, since this is time-based data, it needs to be fixed.
Invalid values are written as nulls.