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Diff — Cartesian coordinate system

Revision #1758 → #2229 · back to history

modifiedCircle of radius 2 as an equation4ab53c152155
FieldFrom #1758To #2229
mathlib.match_kindinvocationspecial_case
provenanceaiai-moderated
addedSigned distance from the originee2108e5fb57
modifiedAffine transformations via matricesb6d6fb5f73cd
FieldFrom #1758To #2229
anchors[{"section":"General matrix form of the transformations","snippet":"All affine transformations of the plane can be described in a uniform way by using matrices."},{"type":"math_alttext","value":"{\\displaystyle {\\begin{pmatrix}x'\\\\y'\\end{pmatrix}}=A{\\begin{pmatrix}x\\\\y\\end{pmatrix}}+b,}"},{"type":"math_alttext","value":"{\\displaystyle A={\\begin{pmatrix}A_{1,1}&A_{1,2}\\\\A_{2,1}&A_{2,2}\\end{pmatrix}}}"},{"type":"math_alttext","value":"{\\displaystyle {\\begin{aligned}x'&=xA_{1,1}+yA_{1,1}+b_{1}\\\\y'&=xA_{2,1}+yA_{2,2}+b_{2}.\\end{aligned}}}"}]
modifiedEuclidean transformations have orthogonal matrix2eed0558efe1
FieldFrom #1758To #2229
anchors[{"section":"General matrix form of the transformations","snippet":"the Euclidean transformations are characterized by the fact that the matrix"},{"type":"math_alttext","value":"{\\displaystyle A_{1,1}A_{1,2}+A_{2,1}A_{2,2}=0}"},{"type":"math_alttext","value":"{\\displaystyle A_{1,1}^{2}+A_{2,1}^{2}=A_{1,2}^{2}+A_{2,2}^{2}=1.}"}]
modifiedTranslation iff A is identityaa29d0647bdc
FieldFrom #1758To #2229
anchors[{"section":"General matrix form of the transformations","snippet":"The transformation is a translation if and only if A is the identity matrix ."},{"type":"math_alttext","value":"{\\displaystyle A_{1,1}A_{2,2}-A_{2,1}A_{1,2}=1.}"}]
modifiedRotation iff A is rotation matrix1b995507cb78
FieldFrom #1758To #2229
anchors[{"section":"General matrix form of the transformations","snippet":"The transformation is a rotation around some point if and only if A is a rotation matrix"},{"type":"math_alttext","value":"{\\displaystyle A_{1,1}A_{2,2}-A_{2,1}A_{1,2}=1.}"}]
modifiedReflection or glide reflection condition565b391d382d
FieldFrom #1758To #2229
anchors[{"section":"General matrix form of the transformations","snippet":"A reflection or glide reflection is obtained when"},{"type":"math_alttext","value":"{\\displaystyle A_{1,1}A_{2,2}-A_{2,1}A_{1,2}=-1.}"}]
modifiedComposition by multiplying matrices191908516801
FieldFrom #1758To #2229
anchors[{"section":"General matrix form of the transformations","snippet":"transformations can be composed by simply multiplying the associated transformation matrices"},{"type":"math_alttext","value":"{\\displaystyle {\\begin{pmatrix}x'\\\\y'\\\\1\\end{pmatrix}}=A'{\\begin{pmatrix}x\\\\y\\\\1\\end{pmatrix}},}"},{"type":"math_alttext","value":"{\\displaystyle A'={\\begin{pmatrix}A_{1,1}&A_{1,2}&b_{1}\\\\A_{2,1}&A_{2,2}&b_{2}\\\\0&0&1\\end{pmatrix}}.}"}]
modifiedAffine transformations of the plane5dba9bcbe4d7
FieldFrom #1758To #2229
anchors[{"section":"Affine transformation","snippet":"Affine transformations of the Euclidean plane are transformations that map lines to lines"},{"type":"math_alttext","value":"{\\displaystyle {\\begin{pmatrix}A_{1,1}&A_{2,1}&b_{1}\\\\A_{1,2}&A_{2,2}&b_{2}\\\\0&0&1\\end{pmatrix}}{\\begin{pmatrix}x\\\\y\\\\1\\end{pmatrix}}={\\begin{pmatrix}x'\\\\y'\\\\1\\end{pmatrix}}.}"}]
addedSwitching one axis reverses orientation82966534143e
modifiedStandard basisa3e1b6b703ae
FieldFrom #1758To #2229
anchors[{"section":"Representing a vector in the standard basis","snippet":"are unit vectors in the direction of the x -axis and y -axis respectively, generally referred to as the standard basis"},{"type":"math_alttext","value":"{\\displaystyle \\mathbf {r} =x\\mathbf {i} +y\\mathbf {j} +z\\mathbf {k} ,}"}]