Move homework #1's octave code into its directory.

[octave.git] / forward_euler.m

diff --git a/forward_euler.m b/forward_euler.m
deleted file mode 100644 (file)
index ec678a1..0000000
--- a/forward_euler.m
+++ /dev/null
@@ -1,43 +0,0 @@
-function coefficients = forward_euler(integer_order, xs, x)
-  ##
-  ## Return the coefficients of u(x0), u(x1), ..., u(xn) as a vector.
-  ## Take for example a first order approximation, with,
-  ##
-  ##   xs = [x0,x1,x2,x3,x4]
-  ##
-  ##   f'(x=x1) ~= [f(x2)-f(x1)]/(x2-x1)
-  ##
-  ## This would return [0, -1/(x2-x1), 2/(x2-x1), 0, 0]. This aids
-  ## the solution of linear systems.
-  ##
-  if (integer_order == 0)
-    df = x;
-    return;
-  end
-
-  if (even(integer_order))
-    offset_b = integer_order / 2;
-    offset_f = offset_b;
-  else
-    ## When the order is odd, we need one more "forward" point than we
-    ## do "backward" points.
-    offset_b = (integer_order - 1) / 2;
-    offset_f = offset_b + 1;
-  end
-
-  ## Zero out the coefficients for terms that won't appear. We compute
-  ## where `x` is, and we just computed how far back/forward we need to
-  ## look from `x`, so we just need to make the rest zeros.
-  x_idx = find(xs == x);
-  first_nonzero_idx = x_idx - offset_b;
-  last_nonzero_idx = x_idx + offset_f;
-  leading_zero_count = first_nonzero_idx - 1;
-  leading_zeros = zeros(1, leading_zero_count);
-  trailing_zero_count = length(xs) - last_nonzero_idx;
-  trailing_zeros = zeros(1, trailing_zero_count);
-
-  targets = xs(first_nonzero_idx : last_nonzero_idx);
-  cs = divided_difference_coefficients(targets);
-
-  coefficients = horzcat(leading_zeros, cs, trailing_zeros);  
-end