Devon wrote:
> I've managed to build an array that's crashing my code.
There's nothing interesting or special about the array. The interpreter
just has a bug; the simple sentence:
$(128!:5) 3 335 $ 0j1
also crashes J. It seems to be sensitive to two features of the array: its
type and shape.
The crash doesn't occur for any boolean, integer, floating point, rational,
or extended int array I tried. So it has to be complex.
It only crashes on complex arrays with particular shape patterns. As you
noticed, it doesn't crash of the table has 334 columns or less; it does
crash if it has 335 or more. It doesn't crash if the table has only one
row, but it does crash if it has more than one row. It doesn't crash on
the ravel of the table (i.e. a rank 1 array), but it does crash if the
array is rank 3 (along with the previous other constraints), etc etc etc.
> I suspected it contained NaNs but my attempt to check it
> crashes J.
Nope. Your array only contains two values:
~. , badarray
_1j_1 _1j_0.96875
and the latter value is rare:
#/.~ , badarray
1003 2
at the indices:
($ #: _1j_1 I.@:~: ,) badarray
1 332
2 333
-Dan
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