大家帮我看看这段程序有没有错,谢谢!

只看该作者 · 发表于 2004-4-14 20:56:00

程序如下,是用来解线性方程的,用的是高斯赛德乐迭代法做的在算三个未知量的时是和答案一致的,四个未知量就有出入,做六个未知量就出错了. 谁能告诉我错在哪里了,是题错还是程序错了. 刚开始学,不足之处请指教。 #include #include #define NN 50 void main() { cout.setf(ios::fixed,ios::floatfield); cout<0 U7 N% v: Q' W+ F0 H int i,j,k; double e,c,T,r; //double x[NN],A[NN][NN],B[NN]; //题目如下：任选一个 //double x[NN]={0,0,0,0},A[NN][NN]={{0,0,0,0},{0,10,-2,-1},{0,-2,10,-1},{0,-1,-2,5}},B[NN]={0,3,15,10}; double x[NN]={0,0,0,0},A[NN][NN]={{0,0,0,0},{0,10,-1,-2},{0,-1,10,-2},{0,-1,-1,5}},B[NN]={0,7.2,8.3,4.2}; //double x[NN]={0,0,0,0,0},A[NN][NN]={{0,0,0,0,0},{0,-5,1,1,2},{0,2,8,1,3},{0,1,-2,-4,-1},{0,-1,3,2,7}},B[NN]={0,-2,-6,6,12}; //double x[NN]={0,0,0,0,0,0,0},A[NN][NN]={{0,0,0,0,0,0,0},{0,1,-1,0,-1,0,0},{0,2,4,-1,0,-1,0},{0,4,-1,4,-1,0,-1},{0,8,0,-1,4,-1,0},{0,12,-1,0,-1,4,-1},{0,16,0,-1,0,-1,4}},B[NN]={0,0,5,-2,5,-2,6}; //double x[NN]={0,0,0,0,0},A[NN][NN]={{0,0,0,0,0},{0,1,0.333,1.5,-0.333},{0,-2.01,1.45,0.50,2.95},{0,4.32,-1.95,0.007,2.08},{0,5.11,-4.00,3.33,-1.11}},B[NN]={0,3.00,2.62,0.130,3.77}; //double x[NN]={0,0,0,0},A[NN][NN]={{0,0,0,0},{0,10,3,1},{0,2,-10,3},{0,1,3,10}},B[NN]={0,14,-5,14}; int N; cout<<"请输入N值:"; cin>>N; cout<7 y% Y( R$ A1 F, ?7 [2 w' a- V7 n cin>>e; /*cout<$ r2 q" D6 f& J7 u8 r- P+ C for(i=1;i<=N;i++) for(j=1;j<=N;j++) { cin>>A[j]; % i9 [. K) U+ \$ p `5 B }' `0 d, H+ E1 z: I cout<3 \ G+ K* `* A! V5 q for(i=1;i<=N;i++) 3 I8 c( G8 R3 w' ^/ _ { + ]/ `2 i6 l. j: k/ V z- ` for(j=1;j<=N;j++) 3 p: U( z# k: }' z& m { , q7 i. @ j5 k5 L* n( @' \3 z cout<[j]<<' '; ; g* h8 @$ j1 |8 l 9 S4 \- w, ?4 h* [1 Q } - I9 M, ] Z% i, [. h cout<2 l8 _0 {+ [& E5 u! Q! N } ( w& q( H' O1 ` d cout<: K) E) d! d! A, ~ for(i=1;i<=N;i++)cin>>B;" d! e W6 g) z for(i=1;i<=N;i++)cout<<<' ';6 [; t- z+ s6 a, V7 N3 [% } cout<' _5 J c6 \; n8 H: p" T for(i=1;i<=N;i++)cin>>x;*/7 l9 B' c: Z4 K4 A1 [ & w1 v1 g( H1 z //cout<<"k"<' K) s c. S( A8 s6 J! t7 X8 P( k! ? //for(i=1;i<=N;i++)cout<<"x["<) r7 H$ V$ B, ]# L2 O1 F r=e;6 p- B% r" z; }. H! | for(k=1;r>=e;k++) ! W& L3 Y& Q% W$ e, C { 4 U$ w9 S' Z. D5 n r=0;" [* f: V( _9 [( i2 u) ^ i=1; ; q2 D& M8 z" C5 i4 V& d a% R for(i=1;i<=N;i++) 6 \0 D* r, l: b: z/ r, U { ! I' B: |4 R8 j, f- s- E2 H T=x;; D$ _! |2 }% I Q$ ] c=0;2 H8 w( g4 ^; }; \/ W# ~ for(j=1;j<=N;j++)3 k7 w* h$ G7 g7 \! k { 5 M' x& | f+ i" l3 [ if(j!=i)c+=(A[j]*x[j]); 5 D+ {) g# G- l7 v: S% H5 M cout<<"第"<7 X: q; q- ^) h X! ~6 e2 V }3 a! ~- P: a# F) V6 o //c1=0;5 v5 ]0 O) S" }. ^ Y/ F+ Z //for(j=1;j<=i-1;j++)c1+=(A[j]*x[j]);3 R$ I" z& e/ ~1 q0 Y; w x=(B-c)/A; _( b+ w ?0 G& f& U cout<<"第"<< s+ v( a t Y$ m" c1 Y* x/ Z1 R; u9 f if((fabs(x-T))>r)r=fabs(x-T);! `5 m8 W: G2 v0 k- c* Y6 p cout<<"第"<0 f; R: S3 D9 v" J } , i+ K* l/ ]9 U4 e cout<8 W9 D' m# {+ a% M5 O8 M //cout<<"k="<% P1 x! u9 H' K5 l* R( }, q 4 y) X: }6 K2 ~ //cout.setf(ios::fixed,ios::floatfield);9 t! I1 v9 m3 e) ^7 z) j for(i=1;i<=N;i++)cout<<"k="<<<' ';//<& H& y" X* C/ ]9 J) H) s5 J2 X ; b; f+ r7 V+ t }cout<5 \8 c* X/ E4 m! e9 _) w: a ( ]. \, }$ q6 z8 C+ n}