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  • 8/2/2019 Bowyer a., woodwark Introduction to Computing With Geometry(Information Geometers,1993)(ISBN 1874728038)(

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    Introduction to

    Computing

    with

    Geometry

    Adrian Bowyer and John Woodwark

    INFORMATION GEOMETERS

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    p l d I W W Q

    s n o m o n q o m v d

    R U o k e n

    n

    y P P S v f

    u

    o o k d n F o m

    s f x I E V U R U P V E H Q E V

    h p o n l l m I I H 7 n l m n

    o m o n l d o n n d F x n

    n m d o n o n D n d ( D n d o m

    o l o n o d F

    s n o m o n q o m v d I W W Q F

    n d d n d o F

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    F F F o m n o n l n F

    h r t o n s o n

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    Contents

    p o o d S

    I F s n o d o n T

    P F q o m I T

    Q F m n d Q I

    R F f n n E n d S I

    S F q n l m l n d T U

    T F l l o n U U

    U F e o m o n V V

    V F o n o m I H P

    W F n o m I I T

    I H F s n o n I P U

    I I F h n n d o ' I Q W

    I P F q o m l o m c c

    I Q F q o m o m m n I S W

    n n d f l o I U Q

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    Foreword

    s n o m o n q o m n g o m n q o m

    o n m o m n l o

    n F o o k m l n d o n o F

    g o m n o m l @ n d n o m l m d d A

    ( l d F r d o o l l o o m o E o E l n o m

    d D m d n m o l F m n o m o

    @ n l m A m o o n o l d

    d o m n n l E

    D o @ m A l F s n

    o m o m n o n o d D n d n l E

    o d l o o o o n l m n

    o l d d d o o o k o n n d F o

    9 k o n l l n F e n n n o d l o n

    o d d o l l o o o d d n o o n o

    l l F

    k n o l d l l d k n d l o n

    d o m n o n o o F o o k

    n o o n o l n d o m n n d D d o ' o o

    l z o n n D m k n d @ n l A

    o o n o m o m n m n F o l d m o l

    o o n o ( n d F

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    1

    Introduction

    s o m o m n o l n m o n y d l l D n o

    n o l n o m y m o n n F w o n l

    ' D l D l y D o n E d m n o n l

    I

    F r o m

    @ n d o l d n l d o m o A j

    l F o m D o D o m o d m n o n o l

    F n o o n l " l m y o d o l l o

    o n d D n o m o n o o d o n m k o l "

    n d o o m o m o l o n d m n n

    m l E d m n o n l n o m o n o n n l F

    f n o o m l D o m o m l l o

    o o m o m n d ' n m o n n m E

    o n F n k d o m m n d o n n D

    n d n m o n D m l n o

    n m l l o n o l l d @ n A m n o o l D n d m o o o n d

    o n o m o l F

    m o d o m n n o m m n Y

    g D f o r t r n n d p r o l o g l n o m l F

    s o n o o n o o o l n D o o l d

    ( n d o m n o o o o m l m n D o o n D

    n d l o m o m o m o n o

    o m n o m F

    g o m n o m l o F s n

    d d d n o n m o m n d o n o m m n o E

    I

    y u p i n n i l i z d o t u ' o u t t i F h o n 9 t u n d t n d

    t d i ' n t n g p t l n d i x p e n s e c e l D t i i l m o t t i n l o u

    o l m F F F F

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    s n t o d u t o n U

    n D o o n l o n D o o n o " o E

    n d F f l o D m o o n d o j

    o l d n o n m n D

    d n ( d z z E F s n o o k D d o n o o l

    o n l l o n D l o o l o m

    o d o m E d d d n n d m n F

    Computer graphics

    g o m

    P

    n n n m o l m n E

    o n o o m n o m F m n n o d o

    o o k d l n j m d l o o o l m l

    X

    e l o m @ f n m 9 l o m A o d n o n

    n F

    g l n n d n d o F

    n o m @ n l d n A F

    E m n d o l o n F

    r d d n E l n 9 n d d d n E 9 l o m F

    l l D o m o o l l m n o n d D k n o n o E

    l o o o X n n l l d n

    o o l F

    q n n l d d l D n d

    n o k d n n m n d ' n d o n D X

    q l o l @ d o 9 A l n F

    p l n m o n F

    p l l n d m o o n o F

    h n m n d o l l o n F

    o o o l m m m o o m l d o m "

    n l o m @ o n n o o o l o n

    d o n ( n E l m n @ f e A m o d A " n d o o m o

    n F r o D l o o l o j D o m o E

    o o m D n o o n o m l m n F

    P

    g l l d i o m n o o n F

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    V s n t o d u t o n

    I @ A " e n m o o l o n n o m E

    n o m @ d d o n A n d n E

    n d l o n m z d n F e m l

    d m o o n o n l o n d n "

    o d " o m l d l o n

    l l F x o m o o n d

    l o n n d o m n o d d D

    m n n n ( n n o n E o m F

    e m m D d d o n l l n

    l o n D m n n @ o o A

    l o n o o m o m n @ o

    n o m o n m " g i s A n o o n n l E

    l o n F

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    s n t o d u t o n W

    Computer vision and image processing

    g o m o n n d m o n l n d n E

    n l n l l F w n m E o n n n

    l d n l o n " o m l D n n o m

    n d m ( l " n d o d o n o F o E

    ( l n l l n @ i A o o n F o m n l

    n d o n o n o n o o m o n o m o

    o n Y m n o o l l o l n o

    F

    Computer-aided design

    g o m E d d d n @ d A n l m Y n l d

    j l o d n n o o m F e l l

    n o m n m n o m o D j m n m

    d n n d o l d m o d l l n m ( n F l o m E d d

    d n m o n n o l n E E l n d E

    o m o n m n o l o n E o l d n o o n z l

    n d l ( l d o n l l l n d o F

    Computer-aided geometric design

    g o m E d d o m d n @ g d A l l d o o

    d o E o m n d F m o d n

    @ o d o m o m n A d o o n o n

    n d n i s n d n l l d m l o D z o

    o o l l o n l o n n m ) Y

    F g o m E d d o m d n o m n n o m m o n

    X d o o o n m o n o l l

    d m o k o n d n n l o o l n F

    d n o o o d z o l F

    Computational geometry

    g o m o n l o m m o l d o o

    d o o m l l o m D n d l l o o l

    0 n D o o d F m n D n l o m n n I H o n d

    o n I H o n D o l o n d o k o n I H H c p o n n D k

    I H H o n d D l l n o d n l o m Y k I H H H H D 9

    o d n2 Y k P H H D 9 O(n log n)D n d o o n F l

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    I H s n t o d u t o n

    n l m o m l d D o m l n

    o m o n l o m o n n m l o n m l D

    o o n F r o D o n n n 0 n

    o l m n l o n D l o n m o o m l d l m n F

    Data visualization

    h l z o n n E m o n m n l o n n d

    d l o l m o n o d l l o n d o m n o

    l l n d o d E n n F l k m d

    d m n o n l y o d Y o n n D l l o l l

    l o m n d o n o m D n d o d E n n

    d o n d ' n o n m n F n l o l m

    l n o m o n @ o n l l d n 9 A m k n o o

    m o d m n o n F e n d o o l m o n n

    l o m 0 n n d l m o n o

    d n o l d n m o l o n F

    Numerical control and robotics

    o n o l o o o m o d n 9 o n o l l n

    o n n o m n o o l o n d l o o F e o m o o n E

    n o m o n n n o l o o m D o o n

    n l l @ l l D n l A Y n d o n n o l d m n l E

    o n ( n l n D l o m n o m

    @ l l D n l A F n o l m o d n m n d l n n n

    ' o o o m n d o d o X n l k l l n

    m o m n o n D j o D n d o ' o m F

    From geometry to program

    o o m o m o n o o m D n d o o o

    n X

    o m t l l o t m o m F

    i o l l o d o l m F

    Geometry algebra

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    p o m o m t t o o m I I

    l l o ' o m d o n o o l m D

    d o E n d E l n m E n d E

    l n c F o n D m ( o n l n

    n d l n n o n l o m n o o d n m @ E

    l l g n o o d n A D n d d d o o l d o ( n d

    n F l l o d o n o l l n

    n l o m D l o m n o n l o m o l o n

    m o n n m n d o m o F n n d d 0 E

    l o o m n o m D n d o n n o

    o n d n o n k n F p o n n o n

    o n n d n o m n n @ o ' o l m A

    d l o l l ( l k l F l l l l

    o l m ( D n o o m ( n d @ l A

    o o n o n n d n o m n Y 9 l o l

    n l D l o F p l l n k o n o d l o o m

    o l o n @ D o o n A o n o l o F

    i n o o d n l o l l D o n o

    n k o Y o n n D o o n l o m

    o o l o m n d n o n @

    l l d o A n n d o m o m l m o n d o n n m Y

    o n n o n d n m n n o E D o

    o E o l D n n o o o o n E

    n o m ( o n F

    Algebra algorithmx o 9 o n o m m o n o n d o o n ( o m E

    m n F r o D o o o n o m o o o m

    o l m o n o n l F p o n n D o m l E

    m

    Q

    o m m o n n d l o o l o m n l E

    o n D l l m o l d ' n o n n d n o n F q o m E

    o l m n d o o d l o n o n E l n o n

    k l m l k Y 9 n m n o m l F

    y n l n l d 0 l n o n z d n d l o n

    l z d o m l m n l F

    i n o D n n l m m k o n o n o o E

    l m F 9 d o d n o l l

    Q

    g l l d l t m o m n o o n F

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    I P s n t o d u t o n

    m l o m n l l o m n o n X y m o l X l m l l Y o l o m l l

    n o o n D n d o k o o d o m o n

    ) F o d o n m k D n o m o l o

    l n o n

    R

    F

    e n l y X l l 9 l l o Y

    l o m d m o d m n o n l o l o n F

    x m l X l l o n n d Y o l m n

    o m l d D n o l o d E o m o l o n

    S

    F n o n

    n d d n m l m o d @ F F l o n A o m l E

    n o o n F

    e o m X n m n Y d o n 9 n n

    o 9 l D n d o k n m l ( o n F

    l l o k l l o m o l o F

    n D n d l l D n d F p o n n D m o m

    o m o o l m D n d n o m l n n l o l o n

    o m l o m F o n d n o l m D n d

    n o l o o m o l o n o n o

    d F

    Algorithm programy l o 9 m o d 0 l o d ' n o m n d d o o d

    o m m n F m o n n d o l d E

    l m n l n o l o n o o m @ n E

    m l o n n X l n l l o n n m l l o n o l l d

    m n o o l Y n m l l X n o o d n o n d l

    n A F m n d o d o d n d o l o E l l o d o n

    o o n Y o m l @ l l l A o m n o o E

    o o n n l o o m n Y n d o l m

    o m m o n F e n D o d n d D d l

    n D o d k D n n 9 n o @ o d d n l D

    F F F A n ( n l o m F

    R

    o u o n l j u t @ I W W Q A Y o m l D n t n i o n t o t n g l i F

    S

    e l o d E o m o l u t i o n i n n t t n i t t n d o n t i t Y

    o m l t o o l o o k o m u l

    b b2 4ac2a

    i l o d E o m o l u t i o n

    t o t o l m o ( n d i n t o o t o u d t i D u t t i n o l o d E o m

    o l u t i o n t o t o l m o ( n d i n t o o t o u i n t i F

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    p o m o m t t o o m I Q

    I @ A " h m n o n l D n l n d o m n o l o m l E

    n d n d n D n d m l d ( n o o

    E d m n o n l 9 F

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    I R s n t o d u t o n

    Dimensional, analytic and combinatorial snags

    r n l o o k d o m o m m n o D k

    o o m o n D n l o l m n o m

    n o o n Y D o m l y n o m

    o l m c s n d o o n o m D n o l n X l o

    o d m n o n D k o n D n d o o m n @ d ' n A o

    o m o n F s l l o n I @ A D n o n

    T

    F

    Dimensional complexity

    q o m o k m k l d ' n l y n d ' n n m o d E

    m n o n F p o n n D n l l l E d n n o d E

    m n o n D l l d l n F @ g o m l o n d l o k F

    d o n x o o l c o d o n 9 o E

    l m o n l o k F A e n d o n d d m n o n n o Y o

    n m o n o l d o E d m n o n l o j D d o n 9

    l m D o n n o m m l Y m d m n o n

    k o l k o m F

    Analytic complexity

    l d d o F i o n n n o

    n n Y k n o d o o m n l k X l n E

    D d D D o n l d D o o D

    l D E d o n l D n o n D n n d n l D

    o m l o l l F F F F o l m m m d l o m m

    o n n o n D l n d D n d o o m n o n o E

    o n m o n d d F l o o l " o D

    o " o o o n d d n o n l o m E

    l D n 9 n o l d F

    Combinatorial complexity

    o m o o o l n l o o d Y n o o d

    n m o o n n o l m F @ o D n 9 o d

    o n n m o n o n d m n o n D o n d n

    T

    s t 9 i n g o m p u t n h p e @ t n n d f i l i o o d t i l o

    o o k n d m n t i o n d i n t t t A D u t t i d i o i i n l l t t i u t l

    t o g l v n D l i F

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    h m n o n l D n l t n d o m n t o l n I S

    o m n k F A e o o d d l o o m o n l o m o

    o n D n d 0 n l o m o d l n l o o m F w o

    o m l d o m n o o m n o l o l m Y

    m n d o m k o m o n n d o F p o m l D

    o ( n d l l d o m d n m o n n D

    n d o o m Y o ( n d D o F

    n o d n3 l o m o F

    e n d d o n l D d ' n D o m n o l l o n

    l o o d ' n o o m o d l n o n o m F

    s @ n m o d m n o n A n o ( n d n o n n

    l n D o n o d o Y n o d l D

    n d o n X l n E l n D l E l D n d l n E l F s

    l l D n d o n D n d o o n F o

    o m m @ y o o o n A Y d o n 9 j

    ' l n o m o m k F s 9 o l n n

    o l l l m o n l o n D n d l o o n k

    o o n o o n F F F F

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    2

    Geometric basics

    Dimensions

    v 9 m o n 9 m l n n n o n d m n o n "

    l o n l n X n o d m n o n " n l n X o n

    d m n o n " n F x o D o n k 9 o n o o '

    n o n d m n o n d o o D o 9 m k n F s n D 9 l o o o l o n d m n o n o n d F m o m k o m m n l l o n d l o o l l o n

    F

    Dimensionality looks easy to extend but it isnt

    y n D o D d m n o n o n d l k o n D o D l @ o

    A " F F m o o m Y 9 n o o d m n o n l

    o k F e d d n d m n o n o o l m l l y n

    n D l o m n D n d

    n d n o l F

    s n o n d m n o n D n @ F F 9 l k o m E

    m n m o n A Y n 9 n o l l n o m

    l l F f D o n o l o m o l m n o n E

    d m n o n l D n d n o n E d m n o n l

    d ( n d o o l n o n d n o d n d n o d D

    n 9 d o n n E d m n o n l F

    s n o d m n o n D n n o n o m n D

    l F w n o m l d @ F F

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    h m n o n I U

    o l o n d A o n E d m n o n l m d d d n

    D o n o k n o n l d m n o n n d d o o n

    @ F F o o d o o l o n A F

    s n d m n o n D o o j n o o n o o m E

    n F y n o n d D n d o j o

    l n l o l d F n o o n E d m n o n l

    @ A n d o E d m n o n l @ A m d d d

    n o F e o l d o n " o m l " n m l o

    l n @ d A n d @ A n d D n l k o l o n D

    n o n o o d n m F

    y n D o o d m n o n o n d l m n F n o

    o D ( " o m o c w n o n n l z d l l

    n o n d m n o n D d o n 9 m n n d o n n n E l m F s n l X

    t m m " n d o m " n d l

    m o n d m n o n D d o n 9 o l o n E

    n d n d n o E d m n o n l X l o

    n l n m o d d ' n l @

    f n o ' 9 o o k A F

    s o n d m n E d m n o n l X o n E

    n m l E l v n d o l d m n E

    o n n d o o ( d m n o n o n o d n

    F f d o n o m n m l E d m n o n l

    n l l d m n o n l n d m n E

    n D n l d m n o n d o F

    v 9 j m d o D n d l o o k o m l l o n F

    m o m m d o o d m n o n F f n

    n n m " l l o l l l " n o

    l n o n n n n n d d o n l l d m n o n F

    o m o D m o l o n l l

    m m l n xD y D z n d m Y n d o m m E l l l F

    n n m l o o n o d m n o n F

    k m l o n o l @ l l

    d o Y o 9 o d D o m k l A X

    (x x0)2 + (y y0)2 r2 = 0.

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    I V q o m t

    e d d n m X n o o n o l d o m o d l l m o n

    n l n F o j o m l n

    x = x0 + f t

    y = y0 + gt,

    t m X o n d o l k F o t o n d l l l o m X

    (x x0 + f t)2 + (y y0 + gt)2 r2 = 0.

    p n X l t z d o D 9 n l l l l n d X n o m m l D n d n o n l k

    F

    v o o k n o o n d F k E

    o n X

    (x x0)2 + (y y0)2 + (z z0)2 r2 = 0. o n o l z t @ o m A D o c x o m o n l l l D l n n d

    o d n o o m l X

    r = t2 + pt + q

    @ p n d q o m o o n n d d o m z0 n d r A Fi n n m l D n o o o n l n k n

    m o n o E d m n o n l n d E d m n o n l

    o n F s n n m o Y m o l o n 9

    o E d m n o n l m o m n o n n o n o m m D o

    n n o o n D m k m d 0 l o n d l F

    n l m o n l z n m o n D o

    n n D o o E d m n o n l o l m D m o

    d m n o n Y n l o o l n

    l l o D n o n n o l l @ F F q l n 9

    I W V V D n d o o d k 9 l o A F

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    o j t o n I W

    Projection

    y n o n n n d o o o n d d m n o n l

    o l m o d d m n o n l o o d o n

    o m o d m n o n F d o n m k

    o m E d m n o n l n D n d l l d o j o n F

    t o n o o d n l d o m o E

    n F p o n n D n n n o o j n n

    D o m l d l o n n

    o n l o j o o d n n d o n n o o d n F

    p D o n n o o o o d l o o d n o X

    n o o d o m l o n l o m F s n o

    o l d o j D o n n D o n l n o n o

    F

    l y o l m n n l l o o j o n

    n F E n l l E k n o n n d n n Y

    o j o d o j d o n o n m o l n D

    o o o n d o o n o m o n o d o @ l D

    o n d A o n n n o n F s n D

    m l n n n o n o @ s l l o n P @ A A F

    o ' o m o j d n o o k n n

    n l d m n o n m n o n d o Y d o o

    d ' n o j o m n o d D n d o

    n n o n " l o n o n "

    o o n d k l F s n D m l n n o

    n n n o o o l m D o d Y

    l o n E o o m d o l o o d o F

    s n o D o j o n n o l F p o n n D n E

    l n n o n o j D o l d m n l o o k

    o n o E d m n o n l d ( n d F s n D

    o n d 0 l D l o o E

    d m n o n l D d o o n o l o E d m n o n l

    Y o k o m ' o o l n o n n m l o E

    j o o m n l d l d o d F n k o n o d

    o d n o n o o n Y n m D o

    n o n o n o n 9 F

    o l n o n o j D n o o m

    n d ( n n n d m n o n @ l n 9 l l E

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    P H q o m t

    P @ A " E n Y o j o j d o n o

    n o n Y n n o n o d E

    m n o F

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    o n t n d t o P I

    k n o n s i g g r p h A F e l o o k o d ( n

    n o n l n d o l o n o

    o j D d o n 9 n d o k n o n o @ d n d

    o n d l A o o j l l l l n d F

    Points and vectors

    s 9 o o m d m n o n " " 9 D

    o o m n o n c o n o o d X j l

    o o o d n l F e o n l o d l m n n o E

    o d n (x , y , . . .) o m o n (0, 0, . . .)F o m m 9 d l k o d l m n o n d D n d m o o o n o E

    l o m o n 9 l d o F ) o n 9 o n

    l l d o F s o d d o o o n D o d ( n n o

    o n D o d d o o o n o o F F F F s n

    l l l o n X

    P P = VV + V = V

    V V = VP + V = P

    P V = PP + P = . . .

    r 3 m o o o n n d ( n d

    I

    F

    v o o k d n o D o d ( n m o m n o

    n d n n ( d d o n F n o

    d n n d d o n n o m l z n o F k E

    d m n o n l o D (xa, ya, za)F p m n d X

    |a

    |= x2a + y2a + z2a.

    o n d n o m l Y 9 l l n m o o

    l F s d d l l o m o n n o o m n E

    d n D n o m l z d D o X l n o I D

    I

    s n o t o d D t t o o i n t n d t o i n o t l o s e d u n d t o E

    t i o n o d d i t i o n n d u t t i o n F

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    P P q o m t

    d o n n n d X

    a =

    xa|a| ,

    ya|a| ,

    za|a|

    .

    o m l l o n c n l m l l o

    o n n D o l o n o o o n F l o o

    l o o m n o X

    d o o d o o o a n d b l d l @ F F

    n m A l o |a||b| cos D n l n

    m F o o d o ( n d o n l n o D

    l l n o F n o d d l o m

    o m o n n o o D j m l l n m o X

    a.b = xaxb + yayb + zazb.

    o o d n n o n d l o

    o n m l l d D l n l o @ o d E

    n A o d o l n X

    a b = ((yazb ybza), (xbza xazb), (xayb xbya)) .

    o o d o o l m l o n n

    l o o 9 o o m o m F n d o n k l D l E

    o l l n d o n o d n m o

    m o o n n F n k o n l n

    m n o n o n o n o Y o d o m l l n

    m o l d o m o n o o d 9 o m n F

    l l n o n l d o m o " o n n d d

    n o n E l n 9 o d m o o m l o n " n l l n o m E

    o m n l l n d 0 n n o n F

    Implicit and parametric geometry

    o o m m o n o m l m n c n o

    o o l o o l l n d o l n y =mx + cD n d n o n d o o n o l d n 9 n l l n D d o x = k Y o D n d n l n n l

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    s m l t n d m t o m t P Q

    l l o mD o o 9 d o ' o m

    x = m

    y + c

    F F F n d l o m o o n o o ' F

    o explicit o n o o o m y = f(x) o x =f(y) @ n d l D z = f(x, y) F A o n l l o d n n o n D n l n m D

    n l E l d " o k n o o n 9 d o l k o n m E

    l F s n o @ g R A l o n l l

    m o d l n m o n l o m l m n

    l l n o l o o k F

    s o o m l o m l m n n o d o

    l n m n o l D n o o X

    Implicit equations

    s m l o n l y l l o n n l n D o n D

    n o o Y o o o n o d ( n

    o n d n o F m l o d o

    o l o m l f(x, y)" o f(x,y,z) n d m n o n " o n F l n m Y 9 n D o n o n

    o n d o o Y 9 o D o n o n

    o F n l o n k o m n o m o n o

    o n E d m n o n l l n D o n n s l l o n P @ A F

    o l o o n m o n o

    o n o o n E d m n o n l l n X o o

    f(x, y) = 0 o f(x,y,z) = 0F l l d m l n d D m l d o n l ( o n F

    l o d o l E D d d o o d n

    n o o l X o n l ( d o n d o n

    l ( d n F o l n o n n n l D o

    o D n d o n m o n d d n d o n o @ n

    o l A o o n o n d d @ n o l n A F

    r o D l E d d D m

    d m n o n l o n l o n n

    m d d d F o D n l n D l l m l o n d Y

    n E d m n o n l D l l d Y n d n o

    d m n o n d o l m @ l z o n A F

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    P R q o m t

    P @ A " g m n X n m l l n m

    o m o o o n d m n o n Y m o n m

    o D o m o n o o d m n o n F

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    s m l t n d m t o m t P S

    Parametric equations

    m o n o n d n o d n o n o m o E

    l D o m D n d l l n xD y " n d z F " n o n o m X

    x = 1(t ,u ,v , . . .)

    y = 2(t ,u ,v , . . .)

    z = 3(. . .)F

    F

    F =F

    F

    F

    o n n k o m n o o o o d n F

    @ s m m xD y D z o o d n D n o l d n o m o n " g W F A e m

    o n l o n m n n o o n o

    n m l o n X n o " l o o k s l l o n P @ A

    n " o n o m o n E d m n o n l l n o o E o E

    d m n o n l F

    r o D n d m n n m o o o d n

    n d n m o m n d n d n l D n o ( d E

    l o n n o o o m l l m n n d

    m o n n d n o k n F

    n o m m n m d o E d m n o n l

    n o E d m n o n l D o l n F f

    m o l m o n n o n o n l E

    m n o n d d m n o n @ l n n d A n d

    n o n o o m n @ A F

    o m m z X

    s m l o n g l o n p d d m n o n l

    n l o

    m o n q n o n o n e n d m n o n l

    l m n

    s n n l D n o o o n n m l n d E

    m o n o o m l m n @ g I I A F r o D

    m l d o o m l n d m o n D n d

    l l n d o o n l o o k n m l o n X

    l n D l n D l n d F s o n m o d l D

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    P T q o m t

    ( n n l o n d o n o m o o m m n d o ' o

    o o X e o m m 9 q o m y F

    The straight line and plane

    m l l n ax + by + c = 0Y m l n X

    x = x0 + f t

    y = y0 + gt.

    f n o n l n ax + by + cz + d = 0 n d

    x = x0 + f1t + f2uy = y0 + g1t + g2u

    z = z0 + h1t + h2u.

    The circle and sphere

    l d n m l o n o l

    (x x0)2 + (y y0)2 r2 = 0, l n d d o X

    (x x0)2 + (y y0)2 + (z z0)2 r2 = 0. n (x0, y0, z0) n d d r F l m o n o l X

    x = x0 + r cos

    y = y0 + r sin

    n d l D n o E o o E l D X

    x = x0 + r cos cos y = y0 + r sin cos

    z = z0 + r sin .

    n l n d l d n d l o n d l F o o l m o m n o n n F p D o o m o n l

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    f o u n d n o m t P U

    o n d o n 9 l k n o n @ k o o l o n A D o o m E

    m o n l l

    cos n d

    sin l E n l o m l X

    sin =2t

    1 + t2

    cos =1 t1 + t2

    where t = tan

    2.

    o n o l m @ e o m m 9 q o m y A Y

    o n l d o 90 o o l F o n d D ( m l o n m z o n

    P

    F q o o n d

    w o l d l l E k n o n o l m Y n

    o m l " o o " n o o l o n X n o

    n n l l l ' o F

    Bounding geometry

    s n D l d o m n n n ( n Y 9 o o l o

    n o D o n o n l F n E l n E

    m n D l D n d o o n d o o o F

    o n d n n o o l n

    o o m n D n d o n F s m l o m

    l ( n D n d o o o o o l o j o F

    e n l m n o m l o m l ( n o o F

    o o n d n d m n d

    o n o o m o j F n o n

    o n d o m l l o o D l "

    n n l n d o m l d " m o o D

    F o o n " n l n

    l n " n d o n o d o o n o m n

    o n l ( d l o d n 9 l o n F s

    o n d n m l o o m o o n D n

    P

    x o t t t t o d p m e t e z t o n t o m n i n X o i o m E

    t @ A n d o n i o n o m i m l i i t t o m t i o m @ t o o i t

    o i m l i i t i z t i o n A F m n o o u n d t i t m i n o l o i l t F

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    P V q o m t

    o m n n o o l d

    n o Y l l n d o n l n o n o o D Fp o m l D o d o n l l n d

    o o d n X

    x = x0,

    x = x1 (x1 > x0),

    y = y0,

    and y = y1 (y1 > y0),

    n n o o o n o m n l X

    x x0x x1y y0y y1

    n d o m n m X

    (x x0) (x x1) (y y0) (y y1).e n o n ( l n d @ o k D " o

    o n d o o n o A n l F

    t o m k n m o o m l d D n o o l d

    d m o n d l n

    m n m m n o n X

    min ((x x0), (x1 x), (y y0), (y1 y)) 0.e l o n o o n n o l d ' n l n o n D n

    m l o n n o n F n o m o n o l k o

    n l n o n @ g S A l l o m n o

    o o m l n o o n m l F g o m n n m l

    n o n E o o o n d D n d n

    o n d o n o E o @ o o n o l d o m "

    s g A o l d m o d l l n D m o n o n d n o

    F F F F

    o m o n c n l o n d d

    m l o n n m o m @ tD uD n d o o n n o o o d n " o m l o n n

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    f o u n d n o m t P W

    m A F e d D o n E d m n o n l

    m D o o n d n n 9 l l o o o m E

    l l F j n n n n d n n d n m

    o " t0 n d t1 F f o o l l n n o n o o o n E d m n o n l m l n o n X

    t t0t t1.

    s n o d m n o n D o m l 9 o n o n F l l D

    m n d D n d

    o d l n d n l @ n d 9 l l A

    n m F e n D n j l m n

    l o o m @ l l 0 n d 1A D n d d o n 9 d o o n n d d n o o m y o o n d F

    o l d o n d n o n n m D n d n l

    o m m o n

    Q

    F o m

    n m d " n o l o n o l l l o o k " o

    n d o n E d m n o n l l 9 F k

    n d n n m n l o n D n l l l l D

    D n o n D n d l l n o

    n l o o o n o n o n d n

    d F e o n D o n n o o E

    o o n d n o n D n m o l F

    n o o o o k n D m o o n n n

    @ o n n n n o m n n o n D o l l n

    g I H A F

    m o n n l o o n d n D m

    k n Y n o D n m l o n D o E o o m E

    n o n o m l o n D n o o F s n

    m k o n o o o o o

    @ F F m A l m n D n d o l E F e

    m l m l o l o n m d o m l n

    m n F e l o n o l y o n o m l D k n o d E

    ( n n n d n d n o d F o l m l n o n D

    Q

    n d d o t o n o o j t i t o u n d d d Y t

    n o t D i n t D u u l l d o n t t i n u t i n u l o u n d i n t o

    t t o m t D u t t t i n u m t i t m n t h e t n l e t s e l f F

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    Q H q o m t

    P @ A " n E 9 o ( n d o o n

    n d o l o n X n m o n o n o d d D

    F

    n n o m l o n F 9 o o d o n m o

    o l D o o n o l n o m o n o n

    o n ( n D n d o n n o m n m o o l o n @

    s l l o n P @ A A Y t o d n o m l l

    ( n l o n o d d o n d m n 9 n d

    o l o n o n o F l o @ l l n

    d m n o n A D n d n n d n o m 9 d

    l k n o n o o o l d n o n D o n d

    m o d l F F F F

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    3

    Parametric

    curves and surfaces

    n n o d m n o n l n n d l

    n d o n o x n d y D n m o n l m tF e l o t n D n l o x n d y n d F s n d m n o n D n d o n l d d n o o n

    o z F l n n X

    x = x0 + f t

    y = y0 + gt

    z = z0 + ht.

    o m @ o m n o A ( n d l l o n k o m

    o n m n o m o n E d m n o n l o o d n m

    n l o o d n t n o o l o E o E d m n o n l F D o n o l n

    I

    o d o

    o m n l o t o l o xD y o z @ n o o o m l o x,y,z o l o tD o n l o n o n o o n d n l o tA F

    s n o d o n d m n o o n o D n

    m n o m o E d m n o n l @ 9 l l t n d u o o d m n o n A n o l F f d o n o n n d

    m o m t, u n o n o o E d m n o n l D n o E d m n o n l n o m X o D E

    o n n d m D E d m n o n l n o m F o n

    n k o g W n o n m o m E

    o n m k o F s m k m o o l l o l

    D o o n 9 n F

    I

    y u D i t2, t3 n d o o n i n t u t i o n F

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    Q P m t u n d u

    v 9 k Y m o m t, u n o E d m n o n l o o d n m @ F F

    x,y,z l A D

    F m o n o l n

    x = x0 + f1t + f2u

    y = y0 + g1t + g2u

    z = z0 + h1t + h2u

    l d d F

    s 9 m n o m o d n o o n n m

    o t o t n d u n o o n F s l l o l n o m o m m k

    o n o n o n o D n d o o n d m

    o l n o m l F s n l

    o n d D n n o n Y n d n

    m n l n @ n l A o l o tD o n n l n t, u l n F y o d o n 9 m n o o o n o @ m o o l A F

    e l m l o n d m o n o

    m k n o n o m @ A n o l n o m l X

    x = a0 + a1t + a2t2 +

    y = F

    F

    F =F

    F

    F

    o D o m D

    x = a0 + a1t + a2u + a3tu + a4t2 + a5u

    2 + a6t2u + a7tu

    2 + a8t3 +

    y = F

    F

    F =F

    F

    F

    e l n l m o n d o n l o l n o m l Y o n k o

    o n m " o k n l l m l " X

    x =a0 + a1t + a2t

    2 + b0 + b1t + b2t2 +

    y =

    F

    F

    F =F

    F

    F

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    s n t o l t o n Q Q

    @ o n d l n D l l F F F A o n l o o n

    o n o n o n l D n

    t = tan2

    m E

    z o n n l F l n o o m

    m n l E d o l n o m l F s n o n @

    o m A n d o o o n D

    n n l E d o n n o F r o D l

    o n l l l o o d o m o l o E d o n D E

    n o d n o m n o n o o o l m X n

    l l o d o o m l o o D o o o D z o c n d o

    o l n o m l n d o m n o D 1 + t2

    m n l m z o n D o m l n n

    o m n o k n d o n o o l F

    s m k n l o d D o D n d o o

    l l n o o n l o n F

    e m o m m d o l m D l o n o o

    l l o n n a D b F c l l o n o n l o D o m m n n D n d m o n o n o d F

    Interpolation

    n l o o k d l n n d l n D d n o o n

    o o X x = x0+f tY n o n d o x = a1+a2t+a3t2+ F o m n k 9 j n o o l D n d 9 D m n o n D n o n o l n

    n d l n D o o 0 n d m n n F k

    l n n D o n n Y (x0, y0, z0) o n t = 0 n d(f ,g ,h) o n d o n o l n F

    n d d n m n o o tD o 0 n n o n m n n F m o o n o l n d

    n l d F m o o m m o n m o d o m k

    o o n o n n D n d m o o m E

    m o n o n n o o n n d n n d o n D l o o

    o n n D d n d D l o d F

    g o n n o m l m n o o o n n o o

    l l d n o l o n F

    s n n l D m o o 0 n n o n o

    o D m o o n n l o m F

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    Q R m t u n d u

    m n o n X

    n d n o o 0 n o j o n n d @ n l 9

    o n o m o n o n o " l A F

    d o n 9 n o o m n o 0 n D d o

    d o m o d o @ o n m A

    o m o d o m o F

    o D l 9 l o o k o o n o l o n n d o o n D

    l n n d l F e l n l o l ( l o o n E

    n X n o o o o n D o o o o n n d

    n n o l F e l d o d o m D o

    n o o o n D o o o n d n n o

    l n D n n o o l n d l n D n d l o d m o Y

    o n ( d D n d o d o d o m l k

    l n F e l o o m n o n D E l n n d l o n E

    o n m l D o n o n n n

    n d n d n o o n n d n n o n n n m n d ' n

    o m n o n F

    m o n l m o l n o m l D n o m l l E

    d o n o o n n d n n l l l E

    o m F

    Lagrange interpolationv n n n o l o n m k o o

    n m o o n F s n o o n o o 0 n n

    o n F p o n n D d l l o o F

    d d l l o o 0 n l l o l n

    o m l n o o n n o 0 n F o n d

    n o o d n o o n " (x , y , . . .)" n d l n m @ A o o n " t , . . ." n o o o n F

    Hermite interpolations n r m n o l o n D d ' n o n o

    o D n d o l m l n o o n o o o o n n d

    n n l o o n n n o l d F

    m n o 0 n d n v n F e E

    l l m o n o n n n o n d

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    s n t o l t o n Q S

    Q @ A " v n n d r m n o l o n d o o n E

    m m n F

    o n D k n o n n n l F

    o o 0 n n o n D Y

    l o n l n n n o o n o n D

    n d I T o 0 n F g n n n o m n

    o m X s l l o n Q @ A F

    The problem of parameterizations n o l n m D d d n m l E

    o n l l " o m z o n " l F

    @ o l m d o n o o l D n l E l d D

    n d X n d o n d o

    d n n d o o n F e n d n o m n 9 l E

    o n l l l o l m o n D o l d

    o n o n l n m o m o n l o m o l m F A

    o D o l m n o l n m D l

    o o n n d n n d o n m o d d D o

    m m l o l d 9 n

    o n D n d m n d l l d o n o d E

    F s n o v n n o l o n D m l o

    o m l l l n o n d F o k

    o n m l n l d Y o o m E

    n n d d F n m z o n l d o

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    Q T m t u n d u

    l n D o l d l k o k n o l n o l l

    n d o n Y n o

    o D n 9 o F y n o l d m l m n

    n o ( n m n " o n D

    l n o m D n d o n n m l d

    o n D n d " m o l n o l l E

    m d Y o l d o l d 0 l n o o o l d

    o n F

    l o l o n o d E l n m z o n D

    m l o n d o n l n o

    E l n m n o n n n m F o o d o k o D

    n o l o n l n o n 9 m l d

    d D n d n o n F p ( n m n n o l k n

    n l n n n o o n @ p n 9 o o k

    g n d o g o m e d d q o m h n o m o

    d l A F

    r m n o l o n D m l o l m o Y n d m

    m m d m n d o d o o m

    dx

    dt F D

    l d o l z o n n o l n n

    d F D l l n l o r m

    o 0 n D m l d l l F 9

    n o o m l l n D o n o m c

    e l l m k n d d d o o l m o n E

    o l o n D l o l o ( n F e n D o

    o k l l l o m D n d l l l m l E

    @ n o m l z o n o l m A F m

    o m D n o d d n d n m l

    o n l l o o n d o F f o n l l d n D

    d 0 l X o d E l n m z o n n l l F

    o n l d o n g o d o v n n d r m

    n o l o n F ( o d o k o v n n n E

    o l n m o l n o m l o o o n n

    d m n o n F o n l l l d n D D n d z F

    m o n ( o n l l 0D n d m E l o n 1Y o 0 n o o l n o m l l l n d n o l D o l D n d o l z Y o l Q o 0 n o

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    s n t o l t o n Q U

    t3 n x n d o o n F m l m d d l o o n o n l l n d n t I n d t P F

    5 n l u ` m t F b

    5 n l u ` t o F b

    G B e o l u t l u m o B G

    5 n @ A @ @ @ A ` H F H A c @ E @ A A X @ A A

    G B e l m o t H E j u t o o u l t o n B G

    5 n e g g @ I F H E T A

    n t l n @ D D z D t I D t P D o l D o l D o l z A

    l o t R D o l R Y

    l o t R D o l R Y

    l o t z R D o l z R Y

    l o t B t I D B t P Y

    {

    l o t D D z D l Y

    n t Y

    G B

    u m t t n t n t o n t t o u t o

    l t I n t P F x o t t t m l t o m

    t n t t n t o o n u l l o t

    t n g m t l n o u l F

    B G

    l a H F H Y

    o @ a I Y ` R Y C C A

    {

    a E E I Y

    a E E I Y

    z a z E z E I Y

    l a l C @ l o t A t @ @ o u l A

    @ B C B C z B z A A Y

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    Q V m t u n d u

    @ a a I A B t I a l Y

    @ a a P A B t P a l Y

    }

    @ l ` e g g A

    {

    n t @ t D

    4 v n X u t o o o t X 7 n 4 D l A Y

    t u n @ I A Y

    }

    B t I a B t I G l Y

    B t P a B t P G l Y

    G B

    g l l t o u t o o m u t t o n t n

    o o n t F

    B G

    @ l n o @ D o l D t I D t P A A t u n @ P A Y

    @ l n o @ D o l D t I D t P A A t u n @ Q A Y

    @ l n o @ z D o l z D t I D t P A A t u n @ R A Y

    t u n @ H A Y

    } G B l n B G

    G B

    o u t o o m u t t o n t n o n

    m n o n o t v n n u t o u o u

    o n t F o l t t l F

    B G

    n t l n o @ D o l D t I D t P A

    l o t R D o l R Y

    l o t B t I D B t P Y

    {

    l o t I D P D Q D t I D t P D t I D t P D n o m D t t Y

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    s n t o l t o n Q W

    I a I E H Y

    P a P E H Y

    Q a Q E H Y

    t I a @ B t I A B @ B t I A Y

    t P a @ B t P A B @ B t P A Y

    t I a t I B @ B t I A Y

    t P a t P B @ B t P A Y

    n o m a @ t P E @ B t P A A B t I Y

    @ @ n o m A ` e g g A

    {

    n t @ t D

    4 v n o X n m n t t o o o t X 7 n 4 D

    n o m A Y

    t u n @ I A Y

    }

    t t a @ E t P C @ B t P A A B t I C @ t P E t P A B @ B t I A Y

    o l Q a @ Q B @ B t P A E P A B t I C

    @ E Q B t P C P A B @ B t I A C

    I B t P E I B @ B t P A G n o m C t t Y

    o l P a @ E Q B @ B t P A C P A B t I C

    @ Q B t P E P A B @ B t I A C

    I B t P C I B @ B t P A G n o m C t t Y

    o l I a @ Q B t P E P A B t I C @ E Q B t P C P A B t I C

    I B t P E I B t P G n o m C t t Y

    o l H a H Y

    t u n @ H A Y

    } G B l n o B G

    o n d o d o m r m n o l n n

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    R H m t u n d u

    d m n o n o o o n o d n o

    n d F o n H n d I D n d d n H n d

    I F o 0 n o n o l n o l n o m l n d n

    o l D o l D n d o l z F l n m m l

    n o v n n n o l o n F

    o m t @ H D I D H D I D o l D o l D o l z A

    l o t H Q D I Q D H Q D I Q Y

    l o t o l R D o l R D o l z R Y

    {

    o m t o @ A Y

    m t o @ H H D I H D H H D I H D o l A Y

    m t o @ H I D I I D H I D I I D o l A Y

    m t o @ H P D I P D H P D I P D o l z A Y

    } G B m t B G

    o m t o @ H D I D H D I D o l A

    l o t H D I D H D I Y

    l o t o l R Y

    {

    l o t D Y

    a I E H E H Y

    a I E H Y

    o l H a H Y

    o l I a H Y

    o l P a Q F H B E Y

    o l Q a E P F H B C Y

    } G B m t o B G

    Surface patches

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    u t R I

    Q @ A " e m Q = F(t, u) d ( n d o n l 0 t 1, 0 u 1F

    m o o m

    x = f1(t, u)

    y = f2(t, u)

    z = f3(t, u)

    @ n l o o o 0 n D Q = F(t, u) E n m l l n n l d n A F

    e n d ( n d o n m o o n o (t, u) m D o d l o o E d m n o n l

    n l X

    0 t 10 u 1.

    m o n n o n o

    o n d o l d m o n d o d j n F

    n m n o X

    h ( n n m o o n d Y o

    k n n g o o n @ g o o n 9 I W T U A D

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    R P m t u n d u

    n o o l o l n d n o o n E

    o m d o n o o n d F

    i l l o o o n k n o n o

    o n d F

    g n o d o n n m

    o d o o o t o m 0 o 3 @ F F 1, t , t2, t3 A n d m o o u @ F F 1, u , u2, u3 A F I T m n o n o o n d n o o o d n X

    x = a0t3u3 + a1t

    3u2 + a2t3u + a3t

    3

    + a4t2u3 + a5t

    2u2 + a6t2u + a7t

    2

    + a8tu3 + a9tu2 + a10tu + a11t+ a12u

    3 + a13u2 + a14u + a15.

    y o o o n d n o n n y n d z D m k n R V m n l l F s 9 o l l d o

    F e d u = 0 D o n n D o n d n o X

    x = a3t3 + a7t

    2 + a11t + a15.

    s n D o n ( d l o t o uD o o E m n o m F

    e l l k n o n o o n o o n d D n d

    o m n n " n d m d D d o E

    F " o o n d F v 9 ( n d n o n o

    n n o u = 0 d o g n o d F p d ' n o uX

    x

    u= 3a0t

    3u2 + 2a1t3u + a2t

    3

    + 3a4t2u2 + 2a5t

    2u + a6t2

    + 3a8tu2

    + 2a9tu + a10t+ 3a12u

    2 + 2a13u + a14.

    n u = 0 n X

    x

    u u=0= a2t

    3 + a6t2 + a10t + a14.

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    u t R Q

    e n o m o n d n d d

    o l n o m l

    P

    d l l m

    u = 0 d Y

    m l o n n l o d

    Q

    F

    s n o m m o n D n o k o d E

    d n d F e n n o n l D o k o j

    o n o o m n d o d o m @ n d m n o n A o

    n o k o l o d d o n l d F @ r E d

    l o o d o d o m D d d o n 9

    n o F A s n d m n d r m E

    n D o o m l o n n l l o l o o n

    o n n l o n n d j n @ o " l o o k n d "

    o o n d n o f z o n o l m A D n

    d o d o m m o E l l d o

    o n X

    2Q(t, u)

    tu.

    s l l o n Q @ A o k o o o F d

    o l o n o o l m d d d o m n F @ 9

    9 l l d E d F F F F A

    p o n o D l 9 l o o k o m n m l F r o d o d c

    m l o m k l n d n o n o E m d F

    v 9 l o o k o m o d o d o F o l d m l o n

    o l xD y n d z n o o D n d k l l n Y 9 n o 0 n D l o n o E m D to u ( d D n d o o l d d o n l o o l l o n F o d o l l o d n o E m l n ( d

    l o uD n t n n F m o 0 n l l o l I T D I T D z I T D

    o o n d o n o n o n d

    o o d n F

    r 9 l Y n o n d o r o n o m

    R

    o E

    P

    p o o m l i t i o n D o n t i n u i t o n i d i t i i u i d F

    Q

    g o n t i n u i t o m t i d i t i i n o t n n t i l o n d i t i o n o m o o t E

    n Y t m i t l o j o i n m o o t l i t t n n t d i t i t t m u t u l

    d i n t m d i t i o n u t d d i ' n t m n i t u d Y o t d i E

    t i m i t n o t m t t l l D u t t o u l d t i l l o m m o n n o m l @ i F F t

    u o u l d l o l l o l n A t t j o i n t F

    R

    r o n e f o m o o l n o m i l a0+ a1t+ a2t2 + a3t

    3+ i a0+ t(a1+

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    R R m t u n d u

    Q @ A " d o d o m o n

    n o l n o n o k o X o n

    r m D n d o n n o n n n o n o o n n

    v n n o l o n F i o n n d

    o d j n D l d n n o o n

    D d o d F

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    u t R S

    o n n F s n E l l o n o u2 n d

    u3

    n n n o l o o n d o

    t2

    n d

    t3

    n F

    l o n o m d o o m n o o n l o n l l d

    m o @ D D z A n d l o t @ D D z A D m o n 9 n n 9

    n d n d o n 9 m o d l F m k n d l

    o n o d l o j o n D l n n d o o n o F

    l o t I T D I T D z I T Y

    G B

    B n t o n t t o u n t n n

    B l o o D o o n 9 t n t l o t o E u t

    B t m t Y n n o R t F

    B G

    l o t H D I D P D Q D H D I D P D Q D

    z H D z I D z P D z Q Y

    l o t t D u D t D D D z Y

    n t D n Y

    H a Q C u B @ P C u B @ I C u B H A A Y

    I a U C u B @ T C u B @ S C u B R A A Y

    P a I I C u B @ I H C u B @ W C u B V A A Y

    Q a I S C u B @ I R C u B @ I Q C u B I P A A Y

    H a Q C u B @ P C u B @ I C u B H A A Y

    I a U C u B @ T C u B @ S C u B R A A Y

    P a I I C u B @ I H C u B @ W C u B V A A Y

    Q a I S C u B @ I R C u B @ I Q C u B I P A A Y

    z H a z Q C u B @ z P C u B @ z I C u B z H A A Y

    z I a z U C u B @ z T C u B @ z S C u B z R A A Y

    z P a z I I C u B @ z I H C u B @ z W C u B z V A A Y

    z Q a z I S C u B @ z I R C u B @ z I Q C u B z I P A A Y

    t(a2+ t(a3+ )))F s t i t m t i n t o l n o m i l i i n l u t d F

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    R T m t u n d u

    t a H F H Y

    t a I F H G @ l o t A @ n E I A Y

    m o @ Q D Q D z Q A Y

    o @ a I Y ` n Y C C A G B n t t o l o o n E I t m B G

    {

    t a t C t Y

    a Q C t B @ P C t B @ I C t B H A A Y

    a Q C t B @ P C t B @ I C t B H A A Y

    z a z Q C t B @ z P C t B @ z I C t B z H A A Y

    l o t @ D D z A Y

    }

    Splines

    s n o l o m k l o n o o m l d

    n l E d o l n o m l F y n o l m o m E

    z o n Y o o l o n m l d o n m k

    m o n d m o l d o n F

    e l o D E d o l n o m l @ o l l o m E

    n d T n d I H A n o o m "

    o n m o m " n d m l n o n n

    o 0 n F @ m o o n n F A

    o o o l o n @ l l D l o o o l o n A o k n o l o

    o m l o o o D n d l o o n

    n d o m F c s D o m

    n k D o m k n o n D o n d o n

    o n o m l n d n d d l l d ( n d Y E

    l l n o F w o n l o m d ( d o

    n D l l o o n Y n d o m n D l l

    n n o o n n D ( d o o l

    o F o n d o n n l o l o l d

    l o l o n n D n d o l l o o m l n o m d ( n d

    F n o m n m z o m m z n l o o m

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    l n R U

    n o o D o 9 l l ( d

    o m l n d n 9 o n o n F

    o d l n o l l n d E

    n D n d 9 l l l l n n o X

    Sequential splining

    m 9 j m d X o d

    m l o o n o n o n d F

    o n o o " l l l

    n d m o m o n " n d n j o n o F

    l l n d l n o d o d o m o m

    o n n m o d 9 l d n l D n d o 9 d

    o m m o n n d D o n o m o l l

    d m n d D n d l l o l o o l l l d l

    o l m n o o m o n l o o m F

    n E d o o o d n n l o n

    D 9 m l Y n m n m n o D o n D

    o o d ( n d n d E o n d o n D n d n d r m n E

    o l o n o m l o F p o D m o d o

    o n o n o m m o n o n Y d d n n m o o m l E

    d D n m o o n d o n o m o n m

    o d d l d n d

    @ s l l o n Q @ A A F D k n o n o d n o

    d n ( n o d n D n d o

    m o d d 0 l o o m F

    Local splining

    o o d o d E d n d n D o l d l k o d m n l l n

    o o m m F y n o d o n o

    k n o o n n m o d o n n " n o

    o n o d j o n n " l n o o F f E l n

    l l m n n d o l D l o n

    o f E l n D j n D o o l l m

    d n l o l n d n l l n n o l o n F f

    n l f E l n D n

    m l d o m o m l D n l X l l D 9

    l l k F

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    R V m t u n d u

    Q @ A " n o n n l d D n o

    o l o o d j o n o o n @ A n d

    o @ A d F m o @ A n d

    o @ A d n o n d n d n F

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    o o n t n u t R W

    s o n n @ o n l l A m l l o l l n X o

    y @ o o ' o e o m m 9 q o m E

    y A F d o ( o m o d l l

    m l m n F s n ' n n n n o E

    d d o m o o n d l d F o d n d n

    o n d D n n n d o o n n o n E n " o l d

    j l o o d ' n m n d D o m l F y n

    n n n d d d ( n d D n n

    n o l d l F

    Global splining

    l w g o F x o o d m n o l

    S

    n

    n l o F n n D o o m m d

    k n o n n D d o n o

    D n d l o o n l o l d D l d n

    n d o n d o n o m n n o n d F

    n ( o o l o o n o 9

    Y o m z n l l o m z d o o l

    D n o j o m m n F d d n n

    o d d ( n n l o l l n o l " l o o m

    n " l o n o l D o o l n m o E

    m n o n o n l l l k l F l o

    l o m l n o o n o o l D o m

    m o d d Y m o n l d o n l z d n d

    l l o d l @ o o k x m l A F

    Types of continuity

    e k n o o l n @ o " o n "

    j o n d A d o n o l l m o m l l n o n E z o d E

    n o F g n D o n n D

    n o n E z o d d Y o m m o n l o n l o o n n d (

    d " n d o l o n d o o " n o d o k n o F

    d o o n n o m m o n l n C0 @ o o n A D

    S

    u n o t l o l l l i n d D u t o m t n i u d o i t o l i n i n

    m o u D t k n o t i n t t o t o i n i d n t n d t n n t

    l n F

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    S H m t u n d u

    C1 D C2 F

    o l d n m n d l n o n l l o n d

    l @ m n d X y = f(x) A n d m z o n " n d o o m ) l " l l F D

    o n n n m d n o m o n n n

    o m n Y n o m z o n o E

    l m n l o n F p E n d o n d E d o m

    o n n o n n o n n n o D n d o n n o

    F o l d m m o n n

    d E l n m z o n Y n n d o D 9

    n o n n @ p o k n d k k l 9 o n m E

    l n m d y o n o d o D l o n l

    o l n o m l o n o l n A F

    n n n l n d o n X

    dQdtdQdt .

    o m n o l l o n o E

    m l D n o l o o d n ( n d o n d

    d X

    =

    dQdt d2

    Qdt2 .dQdt

    3 o n d o m m o o m m o n l d

    o m n n m n D l o l m o

    o n n d " n d n E d " n o l d o

    n F s n d m n o n D m n o o o n n d

    ( d n o m d ' n F o n d d m n o

    m d n d o n l l m n d F s n D ( D

    o n d n d d d o n d m n o n o m

    l o l o o d n l l d p n m D n

    o n o n l o n F e l l D n o

    o n o o o n X p n m o

    o n d 9 F l n n m d o m n o l l

    o ' n o o n o o m n o n F

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