A first version of the assignment

Work 1/scripts/min_bisection.m

@@ -17,6 +17,8 @@ function [a, b, k, n] = min_bisection(fun_expr, alpha, beta, epsilon, lambda)
 %  n:       (number) The calls of objective function fun_expr
 %
 
+
+
 % Error checking
 if alpha > beta || 2*epsilon >= lambda || lambda <= 0
     error ('Input criteria not met')
@@ -25,10 +27,16 @@ end
 % Init
 a = alpha;
 b = beta;
+n = 0;
 fun = matlabFunction(fun_expr);
 
-k=1;
+% wrapper call count function
+function r = count_fun(x)
+    n = n + 1;
+    r = fun(x);
+end
 
+k=1;
 while b(k) - a(k) > lambda
     % bisect [a,b]
     mid = (a(k) + b(k)) / 2;
@@ -37,7 +45,7 @@ while b(k) - a(k) > lambda
     
     % set new search interval
     k = k + 1;
-    if fun(x_1) < fun(x_2)
+    if count_fun(x_1) < count_fun(x_2)
         a(k) = a(k-1);
         b(k) = x_2;
     else
@@ -46,5 +54,4 @@ while b(k) - a(k) > lambda
     end
 end
 
-% Set objective function calls
-n = 2*k;
+end

Work 1/scripts/min_bisection_der.m

@@ -29,8 +29,16 @@ end
 % Init output vectors
 a = alpha;
 b = beta;
+n = 0;
 dfun = matlabFunction(diff(fun_expression));
 
+% wrapper call count function
+% In this case the derivative of the objective function
+function r = count_dfun(x)
+    n = n + 1;
+    r = dfun(x);
+end
+
 k=1;
 while b(k) - a(k) > lambda
     % bisect [a,b]
@@ -38,7 +46,7 @@ while b(k) - a(k) > lambda
     
     % set new search interval
     k = k + 1;
-    df = dfun(x_mid);
+    df = count_dfun(x_mid);
     if df < 0
         a(k) = x_mid;
         b(k) = b(k-1);
@@ -52,6 +60,4 @@ while b(k) - a(k) > lambda
     end
 end
 
-% Update the objctive function calls. In this case the derivative of the
-% function ;)
-n = k;
+end

Work 1/scripts/min_fibonacci.m

@@ -1,4 +1,4 @@
-function [a, b, N, nn] = min_fibonacci(fun_expression, alpha, beta, epsilon, lambda)
+function [a, b, N, n] = min_fibonacci(fun_expression, alpha, beta, epsilon, lambda)
 % Fibonacci method for finding the local minimum of a function.
 %
 % fun_expr: (symbolic expression over x) The symbolic expression of the
@@ -29,8 +29,15 @@ fibonacci = @(n) ( ((1 + sqrt(5))^n - (1 - sqrt(5))^n) / (2^n * sqrt(5)) );
 % Init variables
 a = alpha;
 b = beta;
+n = 0;
 fun = matlabFunction(fun_expression);
 
+% wrapper call count function
+function r = count_fun(x)
+    n = n + 1;
+    r = fun(x);
+end
+
 % calculate number of iterations
 N = 0;
 while fibonacci(N) < (b(1) - a(1)) / lambda
@@ -42,26 +49,33 @@ end
 % will not require to calculate both
 x_1 = a(1) + (fibonacci(N-2) / fibonacci(N)) * (b(1) - a(1));
 x_2 = a(1) + (fibonacci(N-1) / fibonacci(N)) * (b(1) - a(1));
+f1 = count_fun(x_1);
+f2 = count_fun(x_2);
 
 % All but the last calculation
 for k = 1:N-2
     % set new search interval
-    if fun(x_1) < fun(x_2)
+    if f1 <= f2
         a(k+1) = a(k);
         b(k+1) = x_2;
         x_2 = x_1;
+        f2 = f1;
         x_1 = a(k+1) + (fibonacci(N-k-2) / fibonacci(N-k)) * (b(k+1) - a(k+1));
+        f1 = count_fun(x_1);
     else
         a(k+1) = x_1;
         b(k+1) = b(k);
         x_1 = x_2;
+        f1 = f2;
         x_2 = a(k+1) + (fibonacci(N-k-1) / fibonacci(N-k)) * (b(k+1) - a(k+1));
+        f2 = count_fun(x_2);
     end
 end
 
 % Last calculation
 x_2 = x_1 + epsilon;
-if fun(x_1) < fun(x_2)
+f2 = count_fun(x_2);
+if f1 <= f2
     a(N) = a(N-1);
     b(N) = x_1;
 else
@@ -69,6 +83,5 @@ else
     b(N) = b(N-1);
 end
 
-% Set objective function calls
-nn = 2*N -2;
+end
 

Work 1/scripts/min_golden_section.m

@@ -29,36 +29,42 @@ end
 gamma = 0.618;
 a = alpha;
 b = beta;
+n = 0;
 fun = matlabFunction(fun_expression);
 
+% wrapper call count function
+function r = count_fun(x)
+    n = n + 1;
+    r = fun(x);
+end
+
 % calculate x1, x2 of the first iteration, since the following iteration
 % will not require to calculate both
 k=1;
 x_1 = a(k) + (1 - gamma)*(b(k) - a(k));
 x_2 = a(k) + gamma*(b(k) - a(k));
 
-f1 = fun(x_1);
-f2 = fun(x_2);
+f1 = count_fun(x_1);
+f2 = count_fun(x_2);
 while b(k) - a(k) > lambda    
     % set new search interval
     k = k + 1;
-    if f1 < f2
+    if f1 <= f2
         a(k) = a(k-1);
         b(k) = x_2;
         x_2 = x_1;
         f2 = f1;
         x_1 = a(k) + (1 - gamma)*(b(k) - a(k));
-        f1 = fun(x_1);
+        f1 = count_fun(x_1);
     else
         a(k) = x_1;
         b(k) = b(k-1);
         x_1 = x_2;
         f1 = f2;
         x_2 = a(k) + gamma*(b(k) - a(k));
-        f2 = fun(x_2);
+        f2 = count_fun(x_2);
     end
 end
 
-% Set objective function calls
-n = k+1;
+end