TANH

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Syntax

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Scalar

tanh(value)

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Arguments

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Returns

• Type: DOUBLE; FLOAT when the input is evaluated as FLOAT
• Possible values: Values from -1 through 1, including endpoints for infinite inputs.
• NULL behavior: Returns NULL when an argument is NULL.

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Properties

• Approximation bound: No fixed maximum error is guaranteed.

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Usage notes

• Numeric inputs are normally converted to DOUBLE for calculation. An input evaluated as FLOAT keeps FLOAT precision.
• INTEGER and INT mean the same type; STRING means VARCHAR text. NULL can be used with a supported type. Cast NULL explicitly when its type would otherwise be unclear.
• Exact result: Floating-point computation can round the mathematical result.

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Examples

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Value and NULL input

SELECT tanh(CAST(0 AS DOUBLE)) AS "value", tanh(CAST(NULL AS DOUBLE)) AS null_value;

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Positive and negative inputs

SELECT round(tanh(CAST(1 AS DOUBLE)), 6) AS positive_input, round(tanh(CAST(-1 AS DOUBLE)), 6) AS negative_input;

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Limitations

• Query tools may report DOUBLE even when the result is FLOAT. The reported type does not increase the result’s precision.