1 USING: help.markup help.syntax math math.functions sequences ;
4 ARTICLE: "math-vectors" "Vector arithmetic"
5 "Any Factor sequence can be used to represent a mathematical vector, however for best performance, the sequences defined by the " { $vocab-link "specialized-arrays" } " and " { $vocab-link "math.vectors.simd" } " vocabularies should be used."
7 "Acting on vectors by a scalar:"
17 "Vector unary operations:"
21 { $subsection vfloor }
22 { $subsection vceiling }
23 { $subsection vtruncate }
24 "Vector/vector binary operations:"
30 "Saturated arithmetic (only on " { $link "specialized-arrays" } "):"
38 { $subsection vbitand }
39 { $subsection vbitandn }
40 { $subsection vbitor }
41 { $subsection vbitxor }
42 { $subsection vlshift }
43 { $subsection vrshift }
44 "Inner product and norm:"
47 { $subsection norm-sq }
48 { $subsection normalize }
50 { $subsection distance }
53 { $subsection vsupremum }
54 { $subsection vinfimum }
55 { $subsection trilerp }
56 { $subsection bilerp }
58 { $subsection vnlerp }
59 { $subsection vbilerp } ;
64 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } }
65 { $description "Negates each element of " { $snippet "u" } "." } ;
68 { $values { "u" "a sequence of numbers" } { "v" "a sequence of non-negative real numbers" } }
69 { $description "Takes the absolute value of each element of " { $snippet "u" } "." } ;
72 { $values { "u" "a sequence of non-negative real numbers" } { "v" "a sequence of non-negative real numbers" } }
73 { $description "Takes the square root of each element of " { $snippet "u" } "." }
74 { $warning "For performance reasons, this does not work with negative inputs, unlike " { $link sqrt } "." } ;
77 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } }
78 { $description "Takes the " { $link floor } " of each element of " { $snippet "u" } "." } ;
81 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } }
82 { $description "Takes the " { $link ceiling } " of each element of " { $snippet "u" } "." } ;
85 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } }
86 { $description "Truncates each element of " { $snippet "u" } "." } ;
89 { $values { "n" "a number" } { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } }
90 { $description "Adds " { $snippet "n" } " to each element of " { $snippet "u" } "." } ;
93 { $values { "u" "a sequence of numbers" } { "n" "a number" } { "v" "a sequence of numbers" } }
94 { $description "Adds " { $snippet "n" } " to each element of " { $snippet "u" } "." } ;
97 { $values { "n" "a number" } { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } }
98 { $description "Subtracts each element of " { $snippet "u" } " from " { $snippet "n" } "." } ;
101 { $values { "u" "a sequence of numbers" } { "n" "a number" } { "v" "a sequence of numbers" } }
102 { $description "Subtracts " { $snippet "n" } " from each element of " { $snippet "u" } "." } ;
105 { $values { "n" "a number" } { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } }
106 { $description "Multiplies each element of " { $snippet "u" } " by " { $snippet "n" } "." } ;
109 { $values { "u" "a sequence of numbers" } { "n" "a number" } { "v" "a sequence of numbers" } }
110 { $description "Multiplies each element of " { $snippet "u" } " by " { $snippet "n" } "." } ;
113 { $values { "n" "a number" } { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } }
114 { $description "Divides " { $snippet "n" } " by each element of " { $snippet "u" } "." }
115 { $errors "May throw an error if a division by zero occurs; see " { $link "division-by-zero" } "." } ;
118 { $values { "u" "a sequence of numbers" } { "n" "a number" } { "v" "a sequence of numbers" } }
119 { $description "Divides each element of " { $snippet "u" } " by " { $snippet "n" } "." }
120 { $errors "May throw an error if a division by zero occurs; see " { $link "division-by-zero" } "." } ;
123 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "w" "a sequence of numbers" } }
124 { $description "Adds " { $snippet "u" } " and " { $snippet "v" } " component-wise." } ;
127 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "w" "a sequence of numbers" } }
128 { $description "Subtracts " { $snippet "v" } " from " { $snippet "u" } " component-wise." } ;
131 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "w" "a sequence of numbers" } }
132 { $description "Adds and subtracts alternate elements of " { $snippet "v" } " and " { $snippet "u" } " component-wise." }
135 "USING: math.vectors prettyprint ;"
136 "{ 1 2 3 } { 2 3 2 } v+- ."
142 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } { "w" "a sequence of real numbers" } }
143 { $description "Subtracts " { $snippet "v" } " from " { $snippet "u" } " component-wise; any components which become negative are set to zero." } ;
146 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "w" "a sequence of numbers" } }
147 { $description "Multiplies " { $snippet "u" } " and " { $snippet "v" } " component-wise." } ;
150 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "w" "a sequence of numbers" } }
151 { $description "Divides " { $snippet "u" } " by " { $snippet "v" } " component-wise." }
152 { $errors "May throw an error if a division by zero occurs; see " { $link "division-by-zero" } "." } ;
155 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } { "w" "a sequence of real numbers" } }
156 { $description "Creates a sequence where each element is the maximum of the corresponding elements from " { $snippet "u" } " andd " { $snippet "v" } "." }
157 { $examples { $example "USING: math.vectors prettyprint ;" "{ 1 2 5 } { -7 6 3 } vmax ." "{ 1 6 5 }" } } ;
160 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } { "w" "a sequence of real numbers" } }
161 { $description "Creates a sequence where each element is the minimum of the corresponding elements from " { $snippet "u" } " andd " { $snippet "v" } "." }
162 { $examples { $example "USING: math.vectors prettyprint ;" "{ 1 2 5 } { -7 6 3 } vmin ." "{ -7 2 3 }" } } ;
165 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } { "x" "a real number" } }
166 { $description "Computes the dot product of two vectors." } ;
169 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "w" "a sequence of numbers" } }
170 { $description "Adds " { $snippet "u" } " and " { $snippet "v" } " component-wise with saturation." }
174 "USING: math.vectors prettyprint specialized-arrays ;"
175 "SPECIALIZED-ARRAY: uchar"
176 "uchar-array{ 100 200 150 } uchar-array{ 70 70 70 } vs+ ."
177 "uchar-array{ 170 255 220 }"
179 "Without saturation:"
181 "USING: math.vectors prettyprint specialized-arrays ;"
182 "SPECIALIZED-ARRAY: uchar"
183 "uchar-array{ 100 200 150 } uchar-array{ 70 70 70 } v+ ."
184 "uchar-array{ 170 14 220 }"
189 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "w" "a sequence of numbers" } }
190 { $description "Subtracts " { $snippet "v" } " from " { $snippet "u" } " component-wise with saturation." } ;
193 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "w" "a sequence of numbers" } }
194 { $description "Multiplies " { $snippet "u" } " and " { $snippet "v" } " component-wise with saturation." } ;
197 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } { "w" "a sequence of real numbers" } }
198 { $description "Takes the bitwise and of " { $snippet "u" } " and " { $snippet "v" } " component-wise." }
199 { $notes "Unlike " { $link bitand } ", this word may be used on a specialized array of floats or doubles, in which case the bitwise representation of the floating point numbers is operated upon." } ;
202 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } { "w" "a sequence of real numbers" } }
203 { $description "Takes the bitwise and-not of " { $snippet "u" } " and " { $snippet "v" } " component-wise, where " { $snippet "x and-not y" } " is defined as " { $snippet "not(x) and y" } "." }
204 { $notes "This word may be used on a specialized array of floats or doubles, in which case the bitwise representation of the floating point numbers is operated upon." } ;
207 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } { "w" "a sequence of real numbers" } }
208 { $description "Takes the bitwise or of " { $snippet "u" } " and " { $snippet "v" } " component-wise." }
209 { $notes "Unlike " { $link bitor } ", this word may be used on a specialized array of floats or doubles, in which case the bitwise representation of the floating point numbers is operated upon." } ;
212 { $values { "u" "a sequence of real numbers" } { "v" "a sequence of real numbers" } { "w" "a sequence of real numbers" } }
213 { $description "Takes the bitwise exclusive or of " { $snippet "u" } " and " { $snippet "v" } " component-wise." }
214 { $notes "Unlike " { $link bitxor } ", this word may be used on a specialized array of floats or doubles, in which case the bitwise representation of the floating point numbers is operated upon." } ;
217 { $values { "u" "a sequence of integers" } { "n" "a non-negative integer" } { "w" "a sequence of integers" } }
218 { $description "Shifts each element of " { $snippet "u" } " to the left by " { $snippet "n" } " bits." }
219 { $notes "Undefined behavior will result if " { $snippet "n" } " is negative." } ;
222 { $values { "u" "a sequence of integers" } { "n" "a non-negative integer" } { "w" "a sequence of integers" } }
223 { $description "Shifts each element of " { $snippet "u" } " to the right by " { $snippet "n" } " bits." }
224 { $notes "Undefined behavior will result if " { $snippet "n" } " is negative." } ;
227 { $values { "u" "a SIMD array" } { "n" "a non-negative integer" } { "w" "a SIMD array" } }
228 { $description "Shifts the entire SIMD array to the left by " { $snippet "n" } " bytes. This word may only be used in a context where the compiler can statically infer that the input is a SIMD array." } ;
231 { $values { "u" "a SIMD array" } { "n" "a non-negative integer" } { "w" "a SIMD array" } }
232 { $description "Shifts the entire SIMD array to the right by " { $snippet "n" } " bytes. This word may only be used in a context where the compiler can statically infer that the input is a SIMD array." } ;
235 { $values { "v" "a sequence of numbers" } { "x" "a non-negative real number" } }
236 { $description "Computes the squared length of a mathematical vector." } ;
239 { $values { "v" "a sequence of numbers" } { "x" "a non-negative real number" } }
240 { $description "Computes the length of a mathematical vector." } ;
243 { $values { "u" "a sequence of numbers, not all zero" } { "v" "a sequence of numbers" } }
244 { $description "Outputs a vector with the same direction as " { $snippet "u" } " but length 1." } ;
247 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "x" "a non-negative real number" } }
248 { $description "Outputs the Euclidean distance between two vectors." } ;
251 { $values { "u" "a sequence of numbers" } { "v" "a sequence of numbers" } { "axis" "a sequence of 0/1" } { "w" "a sequence of numbers" } }
252 { $description "Using " { $snippet "w" } " as a template, creates a new sequence containing corresponding elements from " { $snippet "u" } " in place of 0, and corresponding elements from " { $snippet "v" } " in place of 1." }
253 { $examples { $example "USING: math.vectors prettyprint ;" "{ 1 2 3 } { 4 5 6 } { 0 1 0 } set-axis ." "{ 1 5 3 }" } } ;
255 { 2map v+ v- v* v/ } related-words
257 { 2reduce v. } related-words
259 { vs+ vs- vs* } related-words