Приложение А
Код программы.
uses crt;
type vec=array [1.4] of real;
mas=array [1.4,1.4] of real;
var a: mas; b, x: vec;
h: real;
i, j, k, n: integer;
inp: text;
Begin.
Clrscr;
n: =4;
assign (inp,'inp. txt');
reset (inp);
read (inp, a [1,1], a [1,2], a [1,3], a [1,4], a [2,1], a [2,2], a [2,3], a [2,4], a [3,1], a [3,2], a [3,3], a [3,4], a [4,1], a [4,2], a [4,3], a [4,4], b [1], b [2], b [3], b [4]);
close (inp);
writeln ('Исходная матрица');
for i: =1 to n do begin.
write (i);
for j: =1 to n do.
write (a [i, j]: 10: 5);
writeln (b [i]: 10: 5) end;
writeln; writeln; writeln;
{исключение переменных}.
for i: =1 to n-1 do.
for j: =i+1 to n do begin.
a [j, i]: =-a [j, i] /a [i, i];
for k: =i+1 to n do.
a [j, k]: =a [j, k] +a [j, i] *a [i, k];
b [j]: =b [j] +a [j, i] *b [i] end;
x [n]: =b [n] /a [n, n];
{нахождение корней}.
for i: =n-1 downto 1 do begin.
h: =b [i];
for j: =i+1 to n do h: =h-x [j] *a [i, j];
x [i]: =h/a [i, i]; end;
writeln ('Корни уравнения');
for i: =1 to n do writeln ('x (', i,') =', x [i]: 10: 5);
writeln;
readkey.