10 CLEAR:R=1200:CLS:PRINT"INTERPOLACION DE LAGRANGE";:GOSUB150:PRINT:DEFCHR$(252)="E8A8E80000":INPUT"Nü de datos a interpolar";N:T=2*N:DIMA(N),B(N),C(T),D(T),E(T),F(T),G(N,N) 20 FORI=0TON-1:INPUT"X"+MID$(STR$(I),2)+"=";A(I),"F(X"+MID$(STR$(I),2)+")=";B(I):NEXT:FORC=0TON-1:U=0:FORJ=0TON-1:IFJ=C THEN40 30 C(U)=-A(J):U=U+1 40 NEXTJ:GOSUB130:M=B(C):FORJ=0TON-1:IFJ=C THEN60 50 M=M/(A(C)-A(J)) 60 NEXTJ:FORI=0TON-1:G(C,I)=G(C,I)*M:NEXTI,C:ERASEF:DIMF(N+1):FORI=0TON-1:FORJ=0TON-1:F(I)=F(I)+G(J,I):NEXTJ,I:CLS:PRINT"El polinomio de interpolacion esF(X)= ";:U=0:FORI=0TON-1:F(I)=ROUND(F(I),-4):U=U+ABS(F(I)):IFF(I)<0THENG$="-" 70 IFF(I)=0THEN120 80 IFF(I)>0THENG$="+" 90 IFN-I>2THENY$=CHR$(144+N-1-I) ELSEY$="" 95 L=F(I):GOSUB160 100 IFN-I>1THENA$=A$+"x" 110 PRINTG$;A$;Y$; 120 NEXTI:END 130 D(0)=1:D(1)=C(0):FORI=1TON-1:E(0)=1:E(1)=C(I):FORX=0TOI:FORY=0TOX:F(X)=D(Y)*E(X-Y)+F(X):NEXTY,X:FORA=1TOI:FORB=A TOI:F(A+I)=D(B)*E(I+A-B)+F(A+I):NEXTB,A 140 FORJ=0TOI+1:D(J)=F(J):F(J)=0:NEXTJ,I:FORJ=0TON-1:G(C,J)=D(J):NEXT:RETURN 150 FORQ=0TO250:NEXT:RETURN 160 IFABSL>0ANDABSL<1E-6THENL=0 170 IFFRACL=0THEN200ELSEA1=ROUND(L*R,-2):A2=ROUND(R,-2) 180 G=2:GOSUB220:G=3:GOSUB220:G=5:GOSUB220 190 A$=MID$(STR$(A1),2)+"/"+MID$(STR$(A2),2):GOTO210 200 A$=MID$(STR$(L),2) 210 RETURN 220 IFFRAC(A1/G)=0ANDFRAC(A2/G)=0THENA1=A1/G:A2=A2/G:GOTO220ELSERETURN