# simd_half3 A vector of three 16-bit floating-point elements. ``` typealias simd_half3 = SIMD3 ``` ## Topics ### Functions to create three-element vectors from other vectors [`simd_make_half3(_:)`](/documentation/simd/simd_make_half3(_:)-52gdy) Returns a new vector from the specified two-element vector, and other elements set to zero. [`simd_make_half3(_:)`](/documentation/simd/simd_make_half3(_:)-4yz0x) Returns a new vector from the specified vector. [`simd_make_half3(_:)`](/documentation/simd/simd_make_half3(_:)-4h0kc) Returns a new vector by truncating the specified four-element vector. [`simd_make_half3(_:)`](/documentation/simd/simd_make_half3(_:)-5nca0) Returns a new vector by truncating the specified eight-element vector. [`simd_make_half3(_:)`](/documentation/simd/simd_make_half3(_:)-9063q) Returns a new vector by truncating the specified 16-element vector. [`simd_make_half3(_:)`](/documentation/simd/simd_make_half3(_:)-64v1) Returns a new vector by truncating the specified 32-element vector. [`simd_make_half3_undef(_:)`](/documentation/simd/simd_make_half3_undef(_:)-1frd1) Returns a new vector from the specified two-element vector, and other elements undefined. ### Functions to create three-element vectors from scalar values [`simd_make_half3(_:)`](/documentation/simd/simd_make_half3(_:)-9gqvo) Returns a new vector with the first element set to a scalar value, and other elements set to zero. [`simd_make_half3(_:_:_:)`](/documentation/simd/simd_make_half3(_:_:_:)) Returns a new vector from the specified scalar values. [`simd_make_half3(_:_:)`](/documentation/simd/simd_make_half3(_:_:)-5wwpl) Returns a new vector from a vector and a scalar value. [`simd_make_half3(_:_:)`](/documentation/simd/simd_make_half3(_:_:)-4svq0) Returns a new vector from a scalar value and a vector. [`simd_make_half3_undef(_:)`](/documentation/simd/simd_make_half3_undef(_:)-6lcqp) Returns a new vector with the first element set to a scalar value, and other elements undefined. ### Functions to create three-element vectors from vectors of other types [`simd_half`](/documentation/simd/simd_half-2rwea) Returns a new vector from the specified vector of 8-bit, signed-integer elements. [`simd_half`](/documentation/simd/simd_half-2rm82) Returns a new vector from the specified vector of 8-bit, unsigned-integer elements. [`simd_half`](/documentation/simd/simd_half-2rr4y) Returns a new vector from the specified vector of 16-bit, signed-integer elements. [`simd_half`](/documentation/simd/simd_half-2rheq) Returns a new vector from the specified vector of 16-bit, unsigned-integer elements. [`simd_half`](/documentation/simd/simd_half-2ry5y) Returns a new vector from the specified vector of 32-bit, signed-integer elements. [`simd_half`](/documentation/simd/simd_half-2roc6) Returns a new vector from the specified vector of 32-bit, unsigned-integer elements. [`simd_half`](/documentation/simd/simd_half-2rz6u) Returns a new vector from the specified vector of 64-bit, signed-integer elements. [`simd_half`](/documentation/simd/simd_half-2royu) Returns a new vector from the specified vector of 64-bit, unsigned-integer elements. [`simd_half`](/documentation/simd/simd_half-2rnty) Returns a new vector from the specified vector of 16-bit, floating-point elements. [`simd_half`](/documentation/simd/simd_half-2rn9m) Returns a new vector from the specified vector of 32-bit, floating-point elements. [`simd_half`](/documentation/simd/simd_half-2rmqe) Returns a new vector from the specified vector of 64-bit, floating-point elements. ### Common functions [`simd_abs(_:)`](/documentation/simd/simd_abs(_:)-8derx) Returns the absolute value of each element in a vector. [`simd_clamp(_:_:_:)`](/documentation/simd/simd_clamp(_:_:_:)-2h8ov) Returns each element in a vector clamped to a specified range. [`simd_equal(_:_:)`](/documentation/simd/simd_equal(_:_:)-9k8m9) Returns true if every element in a vector is exactly equal to the corresponding element in a second vector, and otherwise returns false. [`simd_fract(_:)`](/documentation/simd/simd_fract(_:)-47quw) Returns the fractional part of each element in a vector. [`simd_sign(_:)`](/documentation/simd/simd_sign(_:)-6gppu) Returns the sign of each element in a vector. [`simd_step(_:_:)`](/documentation/simd/simd_step(_:_:)-8w7e) Returns zero for each element in a vector less than a specified edge, and otherwise returns one. ### Reduce functions [`simd_reduce_add(_:)`](/documentation/simd/simd_reduce_add(_:)-2v3th) Returns the sum of all elements in a vector. [`simd_reduce_max(_:)`](/documentation/simd/simd_reduce_max(_:)-4h2m7) Returns the maximum value in a vector. [`simd_reduce_min(_:)`](/documentation/simd/simd_reduce_min(_:)-4685v) Returns the minimum value in a vector. ### Interpolation functions [`simd_mix(_:_:_:)`](/documentation/simd/simd_mix(_:_:_:)-4co2a) Returns an element-wise linearly interpolated value between two vectors. [`simd_smoothstep(_:_:_:)`](/documentation/simd/simd_smoothstep(_:_:_:)-4rnii) Returns an element-wise smoothly interpolated value between two vectors. ### Extrema functions [`simd_max(_:_:)`](/documentation/simd/simd_max(_:_:)-1g1g7) Returns the maximum value of each element in a vector. [`simd_min(_:_:)`](/documentation/simd/simd_min(_:_:)-4rmyw) Returns the minimum value of each element in a vector. ### Reciprocal and reciprocal square root functions [`simd_recip(_:)`](/documentation/simd/simd_recip(_:)-8k0yn) Returns the reciprocal of each element in a vector. [`simd_rsqrt(_:)`](/documentation/simd/simd_rsqrt(_:)-rgh7) Returns the reciprocal square root of each element in a vector. [`simd_precise_recip(_:)`](/documentation/simd/simd_precise_recip(_:)-61jmz) Returns the precise reciprocal of each element in a vector. [`simd_precise_rsqrt(_:)`](/documentation/simd/simd_precise_rsqrt(_:)-znwt) Returns the precise reciprocal square root of each element in a vector. [`simd_fast_recip(_:)`](/documentation/simd/simd_fast_recip(_:)-okeq) Returns the fast reciprocal of each element in a vector. [`simd_fast_rsqrt(_:)`](/documentation/simd/simd_fast_rsqrt(_:)-80xc1) Returns the fast reciprocal square root of each element in a vector. ### Geometry functions [`simd_cross`](/documentation/simd/simd_cross-828tl) Returns the cross product of two vectors. [`simd_dot`](/documentation/simd/simd_dot-p9ir) Returns the dot product of two vectors. [`simd_normalize`](/documentation/simd/simd_normalize-9c7zv) Returns a vector pointing in the same direction of the supplied vector, with a length of 1. [`simd_fast_normalize`](/documentation/simd/simd_fast_normalize-e3y) Returns the fast normalized vector. [`simd_precise_normalize`](/documentation/simd/simd_precise_normalize-4z7hd) Returns the precise normalized vector. [`simd_orient`](/documentation/simd/simd_orient-5jxfm) Tests the orientation of the two supplied vectors. [`simd_project`](/documentation/simd/simd_project-3e81w) Returns the first vector projected onto the second vector. [`simd_precise_project`](/documentation/simd/simd_precise_project-9ry7l) Returns the precise projected vector. [`simd_fast_project`](/documentation/simd/simd_fast_project-99ic5) Returns the fast projected vector. [`simd_reflect`](/documentation/simd/simd_reflect-79zx0) Returns the reflection direction of an incident vector and a unit normal vector. [`simd_refract`](/documentation/simd/simd_refract-5dshi) Returns the refraction direction of an incident vector, a unit normal vector, and an index of refraction eta. ### Vector norm functions [`simd_norm_one`](/documentation/simd/simd_norm_one-xiye) Returns the sum of the absolute values of a vector. [`simd_norm_inf`](/documentation/simd/simd_norm_inf-94803) Returns the maximum absolute value of a vector. ### Length and distance functions [`simd_length`](/documentation/simd/simd_length-3rboq) Returns the length of a vector. [`simd_fast_length`](/documentation/simd/simd_fast_length-56ke1) Returns the fast length of a vector. [`simd_precise_length`](/documentation/simd/simd_precise_length-7azob) Returns the precise length of a vector. [`simd_length_squared`](/documentation/simd/simd_length_squared-3hmac) Returns the square of the length of a vector. [`simd_distance`](/documentation/simd/simd_distance-245n7) Returns the distance between two vectors. [`simd_fast_distance`](/documentation/simd/simd_fast_distance-93wpb) Returns the fast distance between two vectors. [`simd_precise_distance`](/documentation/simd/simd_precise_distance-84o1x) Returns the precise distance between two vectors. [`simd_distance_squared`](/documentation/simd/simd_distance_squared-66q77) Returns the square of the distance between two vectors. ### Logic functions [`simd_select(_:_:_:)`](/documentation/simd/simd_select(_:_:_:)-2ljkl) Returns a vector that contains elements from either the first or second parameter, based on the corresponding element’s high-order bit in the mask. [`simd_bitselect(_:_:_:)`](/documentation/simd/simd_bitselect(_:_:_:)-6ne9u) Returns a vector that contains elements from either the first or second parameter, based on the corresponding element in the third parameter. ### Math functions [`simd_muladd(_:_:_:)`](/documentation/simd/simd_muladd(_:_:_:)-582ze) Returns the multiply-add result for corresponding elements in three vectors. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)