Package dev.frostlake.functions.scalar.vector

Class VectorNormalize

java.lang.Object

dev.frostlake.functions.BuiltInFunction

dev.frostlake.functions.scalar.vector.VectorNormalize

public class VectorNormalize
extends BuiltInFunction

VECTOR_NORMALIZE(v) — the unit vector v / |v|, always a VECTOR(FLOAT, n).

Live-verified:

• VECTOR_NORMALIZE([1,2,3]::VECTOR(FLOAT,3)) is [0.26726124,0.5345225,0.80178374] — the quotients computed in float64 and then NARROWED to float32 elements, not the float64 0.2672612419124244;
• the arithmetic really is float64: [1e-30,2e-30,2e-30] normalizes to [0.33333334,0.6666667,0.6666667], which float32 could not compute (the squares underflow there);
• an INT vector normalizes to a FLOAT one — SYSTEM$TYPEOF of VECTOR_NORMALIZE([1,2,3]::VECTOR(INT,3)) is VECTOR(FLOAT, 3);
• the ZERO vector is NOT a division by zero: VECTOR_NORMALIZE([0,0,0]::VECTOR(FLOAT,3)) is [0.0,0.0,0.0], not NaN.

Constructor Summary

Constructors

Constructor	Description
VectorNormalize()

Method Summary

Modifier and Type	Method	Description
Object	evaluate(List<Object> args)	Computes the function's result over its already-evaluated argument values.
int	getMaxArgCount()	The most arguments a call to this function may pass; Integer.MAX_VALUE marks a variadic function (see BuiltInFunction.isVariadic()).
int	getMinArgCount()	The fewest arguments a call to this function may pass; fewer is an argument-count error.

Methods inherited from class dev.frostlake.functions.BuiltInFunction

approximateRejection, binaryRejection, booleanRejection, evaluate, fileRejection, geoRejection, getName, getReturnType, isVariadic, refusesMissingArgumentsByType, semiStructuredRejection, structuredRejection, temporalRejection, temporalRejection, temporalRejection, textRejection, uuidRejection, vectorRejection

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

VectorNormalize

public VectorNormalize()

Method Details

evaluate

public Object evaluate(List<Object> args)

Description copied from class: BuiltInFunction

Computes the function's result over its already-evaluated argument values. A SQL NULL argument arrives as Java null, and returning null makes the SQL result NULL.

Specified by:

evaluate in class BuiltInFunction

Parameters:

args - the argument values, in call order

Returns:

the function's value for these arguments, or null for SQL NULL

getMinArgCount

public int getMinArgCount()

Description copied from class: BuiltInFunction

The fewest arguments a call to this function may pass; fewer is an argument-count error.

Specified by:

getMinArgCount in class BuiltInFunction

Returns:

the minimum accepted argument count

getMaxArgCount

public int getMaxArgCount()

Description copied from class: BuiltInFunction

The most arguments a call to this function may pass; Integer.MAX_VALUE marks a variadic function (see BuiltInFunction.isVariadic()).

Specified by:

getMaxArgCount in class BuiltInFunction

Returns:

the maximum accepted argument count