I have a large sequence of simple structs, about 5M long. I print its `repr`
before and after sorting. It has lots of data before, but it's all zeroes after
-- except the first element, which is unchanged.
What could explain this behavior? I suspect the merge-sort itself.
import algorithm
type
seq_coor_t* = cint
d_path_data2* = object
d*: seq_coor_t
k*: seq_coor_t
pre_k*: seq_coor_t
x1*: seq_coor_t
y1*: seq_coor_t
x2*: seq_coor_t
y2*: seq_coor_t
proc compare_d_path*(arg1, arg2: d_path_data2): int =
if arg1.d - arg2.d == 0:
return arg1.k - arg2.k
else:
return arg1.d - arg2.d
proc d_path_sort*(path_base: var seq[d_path_data2]) =
echo "sort:", len(path_base), " max:", $max_idx)
path_base.sort(compare_d_path)
#qsort(base, max_idx, sizeof(d_path_data2), compare_d_path);
This was originally in C, and I will probably need to use qsort anyway, so I
can avoid sorting the unused portion of the array. (I wish Nim offered an
ArrayView, compatible with openarray.) But it's disturbing that I cannot can
expected behavior from this standard algorithm. Any ideas?
(Yes, I've run `newSeq` before assigning value. Yes, I use `debug` mode.)
