优化设计第4次课

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2、ab12yy1aa12aa12yy2()aaba22()yf a() 2ab*() 2abba*(ff）黄金分割法的程序框图黄金分割法的程序框图 2( )69f1,70.4 )(xf,31xx2x321xxx 1f2f)(xf),(111fxP),(222fxP),(333fxP3f0a1a2a 1P2P3P2210)(xaxaax (%) 323231032222210212121101)()()(fxaxaaxfxaxaaxfxaxaax (%)02)(21 xaax ， 212aax (#)1a2a0a1a2a 32232223212122212211)()()()(ffxxaxxaff

3、xxaxxa1a2a x,31xxxx)(xf1f2f3f1x2x3x )(xf321213132322212212312322)()()()()()(21fxxfxxfxxfxxfxxfxxx (&) ,31xx2xx42xx 2xx 1x2xx3x1xx2x3x xx 21x2xx3xx4x1x2x4x3x2x4x)(22xff )(44xff 。42ff ,41xx43xx 43ff 42ff ,32xx21xx 42xx 21ff 42ff a) b) c) d) e) f) xx 21xx2x3xx4x1x4x2x3x4x2x)(44xff )(22xff 24ff ,21x

4、x42xx 23xx 42ff23ff 24ff ,34xx41xx 41ff ,31xx,31xx2x1x2x3x2x2x1x3x2312xxx 2x1x3x212312 xxxx 。32312xxx )(x x4x4x4x)(44xf1( )5(1)xf xex13 , 0.5,2.5x x 0.0052)0()0()0()0()0()(21)()()()(xxxfxxxfxfxxf )(xf)0(x)0(x)(x )(xf)(xf)0(x)(xf)(x ) 1 (x0)() 1 ( x 0)()()0() 1 ()0()0( xxxfxf )()()0()0()0() 1 (xfxfxx

5、 )()()()()() 1(kkkkxfxfxx , 2 , 1 , 0 k )0(x)(x )(xf)()0(x )(xf)()0(x ) 1 (x)()0(x x)(xfx )0(x 0 k)()(kxf)()(kxf 。)()()()()() 1(kkkkxfxfxx )() 1(kkxx) 1(* kxx1 kk41664)(234 xxxxxf*x)(xf2( )2f xxx3,50.052( )52f xxx1,100.001 TnxxxX,21 )(minXfnRX (4-1).Xn)(Xf 0,)(*21* TXXnxfxfxfXf（4-2） )0(X0 k)(kS0)()(

6、)( kTkSXf（4-3） 0),(cos)()()()()()()()( kkkkkTkSXfSXfSXf（4-4） )(kX)(kS)(kX图4-2搜索方与梯度方向间的关系k )()()()()(kkkkXfSXf （4-5） ) 1( kX)()() 1(kkkkSXX （4-6） ) 1( kX( )kSk( )kSk ( )kS n)(Xf)(kX)(kS)1( kX)()() 1(kkkkSXX)(kS)()()()()(kkkXfXfS 22221)()( nkxfxfxfXf)(kX)()()()()()1(kkkkkXfXfXX （4-7）k k (1)( )( )( )( )()()min()min ( )kkkkkkkf XfXf XfXf X T( )( )( )( )()()0kkkkfXf Xf X T(1)( )()()0kkf Xf X ()f XkT(1)0kkSS(0)nXR0k ( )kX( )()kf X( )( )()()kkkf XSf X k( )( )( )( )min(kkkkkf XSf XS）( )()kf X*( )kXX*( )()()kf Xf X(1)( )( )kkkkXXS1kk T(1)0kkSS(0)X(0)(0)()Sf X (1)X(1)X(0)S(1)()f XC(0)S(1)