I have tried to reproduce this twice: start the test, wait a while, then
interrupt. Both times the system was uncorrupted.
Can you give more info on when to interrupt to show the error?
Henry Rich
On 10/26/2020 11:24 AM, 'Michael Day' via Programming wrote:
PROGRESS!?
The problem reported under "[Jbeta] J902 exended problem" was NOT with
i-beta in particular.
It is a bit strange, and DOES apply to J901, and perhaps older
versions too. Maybe
something to do with memory allocation for very long extended
representations.
Something happens in the session which alters behaviour, whereby
%4x is initially evaluated as 1r4, but after an interrupt, as shown
below, it returns
a value of 0.
I expect an easier example would give rise to the same effect, but
I'll stick with the
latest manifestation, which is fairly concise.
As I explained earlier, and partly mis-stated, I was exploring, in
Maths-ish notation,
sum{k=1, n} 1 / [(b^(c^k)) . (c^k)]
One of my functions to explore this is
cumSH =: 4 : 0
n =. x
'b c' =. x: y
+/\ % b (]* ^ ) c ^ >: i.n
)
Here's a clip from a session in J 901 :
%4x NB. starts ok
1r4
NB. cumSH soon gets slow - run too many cycles ...
20 cumSH 3 10 NB. interrupted using jbreak.bat...
|break: cumSH
| +/\%b (]*<.@^)c<.@^>:i.n
%4x NB. different value now!
0
datatype%4x NB. still extended, though wrong
extended
JVERSION
Engine: j901/j64avx2/windows
Release-f: commercial/2020-06-11T15:31:28
Library: 9.01.23
Qt IDE: 1.8.6/5.12.7(5.12.7)
Platform: Win 64
Installer: J901 install
InstallPath: c:/d/j901
Contact: www.jsoftware.com
Thanks,
Mike
On 26/10/2020 13:09, 'Michael Day' via Beta wrote:
OK - home again and "solved" this difficulty with extended. Well,
chased it away -
I've no idea _why_ the error arose.
So - in the absence of advice to the contrary, I ran the prescribed
update method,
ie
load'pacman'
'upgrade' jpkg 'jengine'
This method had failed when I first ran it to update to beta-i , the
failure manifesting
itself as an error reported when starting up J902 from its Windows
shortcut. That was
why I had downloaded the zip file and overwritten my J902 folders
with its contents.
However, running the update in the approved manner worked today. The
Windows
JQt shortcut fires up the session without crashing.
Now, I find
1%4x NB. was 0, yesterday !
1r4
1x%4x NB. " " "
1r4
as expected.
Perhaps my attempt on 20/10/20 to overwrite the beta-h installation
with files and folders
from the zip-file went wrong somewhere...
Sorry to have raised this hare, but it was a real anomaly yesterday!
Mike
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