bugGNU Octave - Bugs: bug #52276, Octave cannot display data through...

 
 

bug #52276: Octave cannot display data through pager after too long a data listing on Windows

Submitter:  Philip Nienhuis <philipnienhuis>
Submitted:  Tue 24 Oct 2017 07:04:28 PM UTC
   
 
Category:  Interpreter Severity:  3 - Normal
Priority:  5 - Normal Item Group:  Incorrect Result
Status:  Need Info Assigned to:  None
Originator Name:  Philip Nienhuis Open/Closed:  * Open
Release:  * dev Operating System:  * Microsoft Windows
Fixed Release:  None Planned Release:  None
* Mandatory Fields

Add a New Comment Rich Markup
   

Fri 27 Oct 2017 08:04:06 AM UTC, comment #3: 

That occurred to me as well :-)
After "more on" variable display seems somewhat restored, yes.
But then after one successful listing "data{1}" (actually "data" after the offending command) it doesn't work reliably. I fact I couldn't get variable display to work at all anymore.

The variable "data{1}" contains a number of extremely long text strings w/o newlines that perhaps seem to clobber up the (cmd32.exe-based) terminal on Windows.
After "more on" I could inspect more elements of data{1} but I needed to enter loads of <f>, PG-DN and "arrow down" at random order to get through the listing. Often it stalls and <arrow down> one or more times then helps to display up to the next --less-- prompt.
In addition the "-- less -- (f)orward, (b)ack, (q)uit" prompt only occasionally appears at the bottom, usually it appears somewhere random in the terminal (see attached pic).

It looks like another manifestation of deficiencies of the Windows terminal.
But before simply putting it off like that I'd like to be more sure if that is really true and if there's a solution.



Philip Nienhuis <philipnienhuis>
Group Member
Thu 26 Oct 2017 08:49:24 PM UTC, comment #2: 

After this error occurs, does running "more off" allow subsequent values to print? Does running "more on" again return to the broken state or does it start working again?

(Removed "MXE" from summary field to disambiguate from mxe-octave build system bugs.)

Mike Miller <mtmiller>
Group Member
Tue 24 Oct 2017 07:05:29 PM UTC, comment #1: 

BTW I always disable the pager by "more off"

Philip Nienhuis <philipnienhuis>
Group Member
Tue 24 Oct 2017 07:04:28 PM UTC, original submission:  

This is an issue I encountered irregularly in the last months but couldn't put a finger on.
However while checking if Dan's textscan fixes for bug #52116 would also fix bug #51707 (it appears they do BTW) I found a (for me) reliable way to reproduce the issue.

Steps:

1. Go to bug #51707

2. Execute steps in L.1-11 of the ommand listing in the original report. For convenience, reproduced here:

filename='HB_SNG3.html';
if ~exist(filename,'file')
  %download file
  url='http://web.archive.org/web/20170807165834/https://www.bible.com/nl/bible/75/SNG.3.htb';
  urlwrite(url,filename);
end
%load file
fid=fopen(filename,'rt','n');
data=textscan(fid,'%s','Delimiter','\n');
fclose(fid);
%convert file to a single long string


Then execute the next command (w/o trailing semicolon):

>> data=data{1}

data =
{
  [1,1] = <html data-app-icon="/assets/icons/bible/200/nl-ffe9a1367dc318fe380815df2b772013.pn
g" data-default-locale="en" data-locale="nl" data-logged-in="false" dir="ltr" lang="nl">
:
:    <loooong snip>
:
  [232,1] = <script src="http://web.archive.org/web/20170801165834js_/https://nodejs.bible.co
m/assets/vendor.e22156b1db2119fc8490.js"></script>
  [233,1] = >>


Note that cell array "data" has 1109 items but the listing ends after the start of the 233th.

Next, trying to display any variable value fails until after restart of Octave:

  [232,1] = <script src="http://web.archive.org/web/20170801165834js_/https://nodejs.bible.co
m/assets/vendor.e22156b1db2119fc8490.js"></script>
  [233,1] = >>
>> filename
>> data
>>
>> disp (filename);

>> disp (filename)
>>


(Note the lack of ";" after the commands).

Right-clicking the variable in the workspace and selecting "disp(data)" doesn't work either, see above.

It looks like the amount of data exceeds some buffer after which code to display values is wiped or rendered in-executable.

Philip Nienhuis <philipnienhuis>
Group Member

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attach Files:
   
   
Comment:
   

Attached Files

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -email is unavailable- added by philipnienhuis (Submitted the item)
  •  

    There are 0 votes so far. Votes easily highlight which items people would like to see resolved in priority, independently of the priority of the item set by tracker managers.

    Only group members can vote.

     

    Follow 4 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2018-09-19 mtmiller Carbon-CopyRemoved 80942 -
    2017-10-27 philipnienhuis Attached File- Added bug52276_cmt#3.PNG, #42278
    2017-10-26 mtmiller StatusNone Need Info
        Summary[MXE] Octave cannot display data anymore after too long a data listing Octave cannot display data through pager after too long a data listing on Windows

    Back to the top

    Powered by Savane 3.13-3230.
    Corresponding source code