push

diff --git a/diff.asv b/diff.asv
deleted file mode 100644 (file)
index 41e56bc..0000000
--- a/diff.asv
+++ /dev/null
@@ -1,55 +0,0 @@
-%% Center
-
-D_x_center = diag(0.5*ones(5,1),1) - diag(0.5*ones(5,1),-1);
-D_x_center(1,1) = 1;
-D_x_center(6,6) = 1;
-interval = [0:1/5:1];
-h = 1/5;
-D_x_center
-
-f_x_1 = [1;1;1;1;1;1];
-f_x_2 = interval.';
-f_x_3 = (interval.^2).';
-
-diff1 = 1/h * D_x_center * f_x_1
-diff2 = 1/h * D_x_center * f_x_2
-diff3 = 1/h * D_x_center * f_x_3
-
-%% Forward
-
-D_x_forward = diag(ones(5,1),1) - diag(ones(6,1), 0);
-D_x_forward(6,5) = -1;
-D_x_forward(6,6) = 1;
-
-interval = [0:1/5:1];
-h = 1/5;
-
-f_x_1 = [1;1;1;1;1;1];
-f_x_2 = interval.';
-f_x_3 = (interval.^2).';
-
-diff1 = 1/h * D_x_forward * f_x_1
-diff2 = 1/h * D_x_forward * f_x_2
-diff3 = 1/h * D_x_forward * f_x_3
-
-%% Backwards
-
-D_x_back = D_x_forward;
-
-interval = [0:1/5:1];
-h = 1/5;
-
-f_x_1 = [1;1;1;1;1;1];
-f_x_2 = interval.';
-f_x_3 = (interval.^2).';
-
-diff1 = 1/h * D_x_back * f_x_1
-diff2 = 1/h * D_x_back * f_x_2
-diff3 = 1/h * D_x_back * f_x_3
-
-
-
-%% Bias
-
-bound_low = ((-3*f_x_1(1)) + (4*f_x_1(2)) - (f_x_1(3)))/(2*h)
-bound_up = ((f_x_1(4)) - (4*f_x_1(5)) + (3*f_x_1(6)))/(2*h)
\ No newline at end of file

diff --git a/diff.m b/diff.m
index 64eff1af8ae0a85fbd7460b3f8f28a9f0ef74cd8..64e8bf7dbac9fdd267728622b88abb3b85ad59de 100644 (file)
--- a/diff.m
+++ b/diff.m
@@ -57,19 +57,30 @@ bound_up = ((f_x_3(4)) - (4*f_x_3(5)) + (3*f_x_3(6)))/(2*h)
 
 
 %% EXP
+N = 100;
 
-D_x_center = diag(0.5*ones(5,1),1) - diag(0.5*ones(5,1),-1);
+D_x_center = diag(0.5*ones(N,1),1) - diag(0.5*ones(N,1),-1);
 D_x_center(1,1) = 1;
-D_x_center(6,6) = 1;
+D_x_center(N+1,N+1) = 1;
+
+D_x_forward = diag(ones(N,1),1) - diag(ones(N+1,1), 0);
+D_x_forward(N+1,N) = -1;
+D_x_forward(N+1,N+1) = 1;
 
-N = 5;
 interval = [0:1/N:1];
 h = 1/N;
-
+f = zeros(length(interval), 1);
 f_prim = zeros(length(interval), 1);
 for i=1:length(interval)
+    f(i) = 4*exp(sin(4*interval(i)));
     f_prim(i) = 4*exp(sin(4*interval(i)))*cos(4*interval(i));
 end
+
+D_x_center
+interval
+f
+
+approx = (1/h) * D_x_center * f
 f_prim
 
 
@@ -84,3 +95,4 @@ f_prim
 
 
 
+