Hi Kacper,
I am aware of the non-transitivity of = when ⎕CT ≠ 0. However, the
algorithm used in GNU APL is essentially the same as in the ISO
standard. The result is sometimes puzzling.
The difference between GNU APL and ISO is that the ISO
algorithm has, in the worst case, quadratic runtime, whi
Actually, while the algorithm used for 20≥⍴ works well with
characters or integers (once you fix the direction of
inequality), I don't think it's actually correct at all for
non-zero ⎕CT because tolerant equality is not transitive.
Consider this:
X←1+0 1 2 5 4 3×(⎕CT←1E¯9)÷2
∪19
I'd like to contribute the two attached files to the gnu-apl project.
Quad_FIO.tc includes test cases for FIO∆pipeto and FIO∆pipefrom, while
FILE_IO.apl has a revised version of FIO∆pipeto discovered during testing.
Bill Daly
#!/usr/local/bin/apl --script --
Hello,
Unique with argument of 20 or more items gives results
in an incorrect order:
∪'abbbaaa'
ab
∪'abbb'
ba
Or even with wrong set of distinct elements:
(A B C)←1+¯1 0 1×(⎕CT←1E¯9)÷2
∪19↑B A B C
1 0
∪20↑B A B C
0.95 1.000
