docs-v2/content/flux/v0/stdlib/universe/bool.md

title	description	menu	weight	flux/v0/tags	introduced
bool() function	`bool()` converts a value to a boolean type.	flux_v0_ref name parent identifier bool universe universe/bool	101	type-conversions	0.7.0

bool() converts a value to a boolean type.

Function type signature

(v: A) => bool

{{% caption %}} For more information, see Function type signatures. {{% /caption %}}

Parameters

v

({{< req >}}) Value to convert.

Examples

• Convert strings to booleans
• Convert numeric values to booleans
• Convert all values in a column to booleans

Convert strings to booleans

bool(v: "true")

// Returns true
bool(v: "false")// Returns false

Convert numeric values to booleans

bool(v: 1.0)

// Returns true
bool(v: 0.0)

// Returns false
bool(v: 1)

// Returns true
bool(v: 0)

// Returns false
bool(v: uint(v: 1))

// Returns true
bool(v: uint(v: 0))// Returns false

Convert all values in a column to booleans

If converting the _value column to boolean types, use toBool(). If converting columns other than _value, use map() to iterate over each row and bool() to convert a column value to a boolean type.

data
    |> map(fn: (r) => ({r with powerOn: bool(v: r.powerOn)}))

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Input data

_time	powerOn	*tag
2021-01-01T00:00:00Z	1	t1
2021-01-01T00:00:10Z	1	t1
2021-01-01T00:00:20Z	0	t1
2021-01-01T00:00:30Z	1	t1
2021-01-01T00:00:40Z	0	t1
2021-01-01T00:00:50Z	0	t1

_time	powerOn	*tag
2021-01-01T00:00:00Z	0	t2
2021-01-01T00:00:10Z	1	t2
2021-01-01T00:00:20Z	0	t2
2021-01-01T00:00:30Z	1	t2
2021-01-01T00:00:40Z	1	t2
2021-01-01T00:00:50Z	0	t2

Output data

_time	powerOn	*tag
2021-01-01T00:00:00Z	true	t1
2021-01-01T00:00:10Z	true	t1
2021-01-01T00:00:20Z	false	t1
2021-01-01T00:00:30Z	true	t1
2021-01-01T00:00:40Z	false	t1
2021-01-01T00:00:50Z	false	t1

_time	powerOn	*tag
2021-01-01T00:00:00Z	false	t2
2021-01-01T00:00:10Z	true	t2
2021-01-01T00:00:20Z	false	t2
2021-01-01T00:00:30Z	true	t2
2021-01-01T00:00:40Z	true	t2
2021-01-01T00:00:50Z	false	t2

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