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Dot ​

Generated from the engine's own definition: compute-engine's symbol, which we neither extend nor document by hand.

Dot product (vector inner product) or matrix product.

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Dot(list<tuple> | matrix | tuple | vector, list<tuple> | matrix | tuple | vector) -> valueDot product (vector inner product) or matrix product.
Typed signatures
TypePackageApplies
(list<tuple> | matrix | tuple | vector, list<tuple> | matrix | tuple | vector) -> valuecompute-enginealways
(expression<ModularMatrix> | list<tuple> | matrix | matrix | string | tuple | tuple | vector | vector, expression<ModularMatrix> | list<tuple> | matrix | matrix | string | tuple | tuple | vector | vector) -> expression<ModularMatrix> | matrix | number | value | vectormodularreplaces compute-enginealways

Domain: Compute engine

Examples

Basic #

Vector dot product, symbolic

live ↗
InDot([a,b,c],[x,y,z])\mathrm{Dot}(\bigl\lbrack a, b, c\bigr\rbrack, \bigl\lbrack x, y, z\bigr\rbrack)Outax+by+czax+by+cz

Matrix times vector gives a vector

live ↗
InDot([[a,b],[c,d]],[x,y])\mathrm{Dot}(\bigl\lbrack\bigl\lbrack a, b\bigr\rbrack, \bigl\lbrack c, d\bigr\rbrack\bigr\rbrack, \bigl\lbrack x, y\bigr\rbrack)Out[ax+by,cx+dy]\bigl\lbrack ax+by, cx+dy\bigr\rbrack

Vector times matrix uses the columns

live ↗
InDot([x,y],[[a,b],[c,d]])\mathrm{Dot}(\bigl\lbrack x, y\bigr\rbrack, \bigl\lbrack\bigl\lbrack a, b\bigr\rbrack, \bigl\lbrack c, d\bigr\rbrack\bigr\rbrack)Out[ax+cy,bx+dy]\bigl\lbrack ax+cy, bx+dy\bigr\rbrack
Scope #

Integer vectors give an exact scalar

live ↗
InDot([1,2,3,4,5],[1,8,9,0,−1])\mathrm{Dot}(\bigl\lbrack1, 2, 3, 4, 5\bigr\rbrack, \bigl\lbrack1, 8, 9, 0, -1\bigr\rbrack)Out3939

Matrix product with exact rational entries

live ↗
InDot([[2,0,0],[0,0,352],[0,352,0]],[[8,0,0],[0,0,10],[0,10,0]])\mathrm{Dot}(\bigl\lbrack\bigl\lbrack2, 0, 0\bigr\rbrack, \bigl\lbrack0, 0, \frac{35}{2}\bigr\rbrack, \bigl\lbrack0, \frac{35}{2}, 0\bigr\rbrack\bigr\rbrack, \bigl\lbrack\bigl\lbrack8, 0, 0\bigr\rbrack, \bigl\lbrack0, 0, 10\bigr\rbrack, \bigl\lbrack0, 10, 0\bigr\rbrack\bigr\rbrack)Out[[16,0,0],[0,175,0],[0,0,175]]\bigl\lbrack\bigl\lbrack16, 0, 0\bigr\rbrack, \bigl\lbrack0, 175, 0\bigr\rbrack, \bigl\lbrack0, 0, 175\bigr\rbrack\bigr\rbrack
live ↗
InDot([a,b,c],[0,b,d+k])\mathrm{Dot}(\bigl\lbrack a, b, c\bigr\rbrack, \bigl\lbrack0, b, d+k\bigr\rbrack)Outb2+cd+ckb^2+cd+ck
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Examples6
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