Roots of a function: Difference between revisions

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@@ Line 286: / Line 286: @@
   END DO</lang>
-=={{header|GNU Octave}}==
-If the equation is a polynomial, we can put the coefficients in a vector and use ''roots'':
-<lang matlab>a = [ 1, -3, 2, 0 ];
-r = roots(a);
-% let's print it
-for i = 1:3
-  n = polyval(a, r(i));
-  printf("x%d = %f (%f", i, r(i), n);
-  if (n != 0.0)
-    printf(" not");
-  endif
-  printf(" exact)\n");
-endfor</lang>
-Otherwise we can program our (simple) method:
-{{trans|Python}}
-<lang matlab>function y = f(x)
-  y = x.^3 -3.*x.^2 + 2.*x;
-endfunction
-step = 0.001;
-tol = 10 .* eps;
-start = -1;
-stop = 3;
-se = sign(f(start));
-x = start;
-while (x <= stop)
-  v = f(x);
-  if ( (v < tol) && (v > -tol) )
-    printf("root at %f\n", x);
-  elseif ( sign(v) != se )
-    printf("root near %f\n", x);
-  endif
-  se = sign(v);
-  x = x + step;
-endwhile</lang>
 =={{header|J}}==
@@ Line 406: / Line 366: @@
  Out[6]= x==0||x==1||x==2
 (note that this doesn't yield a "solution" but a different expression that expresses the same thing as the original)
+=={{header|Octave}}==
+If the equation is a polynomial, we can put the coefficients in a vector and use ''roots'':
+<lang matlab>a = [ 1, -3, 2, 0 ];
+r = roots(a);
+% let's print it
+for i = 1:3
+  n = polyval(a, r(i));
+  printf("x%d = %f (%f", i, r(i), n);
+  if (n != 0.0)
+    printf(" not");
+  endif
+  printf(" exact)\n");
+endfor</lang>
+Otherwise we can program our (simple) method:
+{{trans|Python}}
+<lang matlab>function y = f(x)
+  y = x.^3 -3.*x.^2 + 2.*x;
+endfunction
+step = 0.001;
+tol = 10 .* eps;
+start = -1;
+stop = 3;
+se = sign(f(start));
+x = start;
+while (x <= stop)
+  v = f(x);
+  if ( (v < tol) && (v > -tol) )
+    printf("root at %f\n", x);
+  elseif ( sign(v) != se )
+    printf("root near %f\n", x);
+  endif
+  se = sign(v);
+  x = x + step;
+endwhile</lang>
 =={{header|Perl}}==