var
  s, s1, p, p1, xx, H, J1, a: real;
  k, i, n, j, ii, e1, f1, n1: integer;
  x, y, z, z1: array [1..50] of real;


begin
  repeat
    clrscr;
    write('Vvedite kolichestvo tochek: ');
    readln(n);
    if n<=0 then
      begin
        writeln;
        write('Vvodit nado polozhitelnoe chislo! Nazhmite Enter');
        readln;
      end;
  until n>0;
  writeln;
  for i:=1 to n do
    begin
      Write('vvedite x',i,': '); Readln(x[i]);
      Write('vvedite y',i,': '); Readln(y[i]);
      writeln;
    end;
  write('  Vvedite x*:'); Readln(xx);
  s:=y[1];
  for i:=2 to n do
    begin
      p:=1; s1:=0;
      for j:=1 to i do
        begin
       if j=i then
            goto l;
          p:=p*(xx-x[j]);
          l:
          p1:=1;
          for k:=1 to i do
            begin
              if j<>k then
                p1:=p1*(x[j]-x[k]);
            end;
          p1:=y[j]/p1; s1:=s1+p1;
        end;
      p:=p*s1; s:=s+p;

if j=i then
            goto l;
          p:=p*(xx-x[j]);
          l:

Цитата(Dark_san @ 21.04.2010 2:45)

if j=i then
            goto l;
          p:=p*(xx-x[j]);
          l:

if j<>i then p:=p*(xx-x[j]);

Меня препод съест

Цитата(Lapp @ 21.04.2010 4:05)

Гм?..

if j<>i then p:=p*(xx-x[j]);

И правильно сделает, приятного ему аппетита..

if j=i then
            goto l;
          p:=p*(xx-x[j]);
          l:
          p1:=1;

if j<>i then p:=p*(xx-x[j]) else
 p1:=1;

const
  n=11;

const
  x0: double= 0.01;
  h: double= 0.05;
  y: array[0..n]of double = (
    0.99,
    0.95,
    0.91,
    0.87,
    0.84,
    0.80,
    0.77,
    0.74,
    0.71,
    0.68,
    0.65,
    0.63
  );

function Prod(t: double; k: integer): double;  // t(t-1)...(t-k)
begin
  if k=0 then Prod:=t else Prod:=t*Prod(t-1,k-1)
end;


function FinDif(k,i: integer): double;   // finite difference
begin
  if k=0 then FinDif:=y[i] else FinDif:=FinDif(k-1,i+1)-FinDif(k-1,i)
end;


function NewtonPol(x: double): double;
var
  k: integer;
  p,t,f: double;
begin
  p:=y[0];
  t:=(x-x0)/h;
  f:=1;
  for k:=1 to n do begin
    f:=f*k;
    p:=p+Prod(t,k-1)*FinDif(k,0)/f
  end;
  NewtonPol:=p
end;

begin
  WriteLn(NewtonPol(0.492):8:5)
end.

Цитата(Dark_san @ 22.04.2010 0:31)

)) бывает и такое

 Program Nyuton;
uses crt;
var
		str: string;
		s, s1, p, p1, xx,  a: real;
		k, i, n, j, ii, e1, f1, n1: integer;
		x, y, z : array [1..50] of real;



begin
  repeat
    clrscr;
    write('Vvedite kolichestvo tochek: ');
    readln(n);
    if n<=0 then
      begin
        writeln;
        write('Vvodit nado polozhitelnoe chislo! Nazhmite Enter');
        readln;
      end;
  until n>0;
		writeln;
  for i:=1 to n do
    begin
      Write('vvedite x',i,': '); Readln(x[i]);
      Write('vvedite y',i,': '); Readln(y[i]);
      writeln;
    end;
	write('  Vvedite x*:'); Readln(xx);
	s:=y[1];
  for i:=2 to n do
    begin
      p:=1; s1:=0;
      for j:=1 to i do
        begin
          if j<>i then p:=p*(xx-x[j]);
          
          p1:=1;
          for k:=1 to i do
            begin
              if j<>k then
                p1:=p1*(x[j]-x[k]);
            end;
          p1:=y[j]/p1; s1:=s1+p1;
        end;
      p:=p*s1; s:=s+p;
    end;
  writeln;
  for i:=1 to n do
	begin
			writeln('X[',i,']',x[i]4,'  Y[',i,']',y[i]4);
	end;
		write('  Otvet f(x*)=');
		textcolor(18);
		writeln(s:5:3);
		writeln;
		textcolor(15);
		write('  Nazhmite Enter');
  
  readln;
  end

Цитата(Dark_san @ 22.04.2010 21:06)

Не забраковала, а потерялась )

Где там игрики?
куда икс вводить нашла
а вот с игриками- проблема

  y: array[0..n]of double = (
    0.99,
    0.95,
    0.91,
    0.87,
    0.84,
    0.80,
    0.77,
    0.74,
    0.71,
    0.68,
    0.65,
    0.63
  );

function FinDif(k,i: integer): double;
var
   a,b: double;
begin
  if k=0 then FinDif:=y[i] else begin
     a:=FinDif(k-1,i+1);
     b:=FinDif(k-1,i);
     FinDif:=a-b
  end
end;

    f:=f/k;
    p:=p+f*Prod(t,k-1)*FinDif(k,0)