vb设计-计算方法上机

非线性方程数值方法1、固定点迭代求解方程的近似值，初始值为，迭代式为XG0X1NNXGFUNCTIONK,X1,ERR,XFIXPTG,X0,TOL,MAXLINPUTGISTHEITERATIONFUNCTIONINPUTASASTRINGGX0ISTHEINITIALGUESSFORTHEFIXEDPOINTTOLISTHETOLERANCEMAXLISTHEMAXIMUMNUMBEROFITERATIONSOUTPUTKISTHENUMBEROFITERATIONTHATWERECARRIEDOUTX1ISTHEAPPROXIMATIONTOTHEFIXEDPOINTERRISTHEERRORINTHEAPPROXIMATIONXCONTAINSTHESEQUENCEXNX1X0FORK2MAXLXKFEVALG,XK1ERRABSXKXK1RELERRERR/ABSXKEPSX1XKIFERR0,BREAK,ENDMAXL1ROUNDLOGBALOGDELTA/LOG2FORK1MAXLCAB/2YCFEVALF,CIFYC0ACBCELSEIFYBYC0BCYBYCELSEACYAYCENDIFBA02X000105PIYXSINX1PLOTX,Y,RHOLDONPLOTX,0,GFINLINEXSINX1C,ERR,YCBISECTF,0,2,0013、牛顿拉夫申迭代使用初始近似值，利用迭代式，计算0X,21,1KXFXK函数的根的近似值。0XFFUNCTIONX0,ERR,K,YNEWTONF,DF,X0,DELTA,EPSILON,MAXLINPUTFISTHEOBJECTFUNCTIONINPUTASASTRINGFDFISTHEDERIVATIVEOFFINPUTASASTRINGDFX0ISTHEINITIALAPPROXIMATIONTOAZEROOFFDELTAISTHETOLERANCEFORX0EPSILONISTHETOLERANCEFORTHEFUNCTIONVALUESYMAXLISTHEMAXIMUMNUMBEROFITERATIONSOUTPUTXISTHENEWTONRAPHSONAPPROXIMATIONTOTHEZEROERRISTHEERRORESTIMATEFORX0KISTHENUMBEROFITERATIONSYISTHEFUNCTIONVALUEFX0FORK1MAXLX1X0FEVALF,X0/FEVALDF,X0ERRABSX1X0RELERR2ERR/ABSX1DELTAX0X1YFEVALF,X0IFERRTOLHH/2S0FORK1MXAH2K1SSFEVALF,XENDRJ1,1RJ,1/2HSM2MFORK1JRJ1,K1RJ1,KRJ1,KRJ,K/4K1ENDERRABSRJ,JRJ1,K1ENDQUADRJ1,J1【例】用龙贝格积分计算。FINLINEX2X1COSX2/0COS1DXXA0BPI/2N5TOL00001R,QUAD,ERR,HROMBERGF,A,B,N,TOL积分准确值I_EXACTINTX2X1COSX,0,PI/2I_EXACTVPAI_EXACT,105、自适应辛普生积分辛普生公式子程序SRULE用于实现自适应积分过程中产生的子区间上的辛普生公式，其中。04030BFCFAFHDXFBA2/0BACFUNCTIONZSRULEF,A0,B0,TOL0INPUTFISTHEINTEGRANDINPUTASASTRINGFA0ANDB0ARELOWERANDUPPERLIMITSOFINTEGRATIONTOL0ISTHETOLERANCEOUTPUTZISA1X6VECTORA0B0SS2ERRTOL1HB0A0/2CZEROS1,3CFEVALF,A0A0B0/2B0SHC14C2C3/3S2STOL1TOL0ERRTOL0ZA0B0SS2ERRTOL16、高斯勒让德积分,NKKBATFADTFADXF112其中。KKTAT,2FUNCTIONQUADGUASSF,A,B,XK,AKINPUTFISTHEINTEGRANDINPUTASASTRINGFAANDBARELOWERANDUPPERLIMITSOFINTEGRATIONXKISTHE1XNVECTOROFABSCISSASFROMTABLEAKISTHE1XNVECTOROFWEIGHTSFROMTABLEOUTPUTQUADISTHEQUADRATUREVALUENLENGTHXKTZEROS1,NTAB/2BA/2XKQUADBA/2SUMAKFEVALF,T【例】利用两点高斯勒让德积分计算。109861LN32DXFINLINE1/