Re: [LON-CAPA-users] Duplicated ids found (SOLVED!)

[Itay Furman]

Hi,

As suggested by Raymond I manually change the id in the imported 
library file, and that solved the problem.

In my original problem file I did not include id attribute for the 
import tag.  The id="11" was added automatically during publication.
Although the automatic addition of id attributes is documented, I 
missed that point until the error hit me.

Thank again,
Itay


On Sun, 27 Oct 2013, Itay Furman wrote:

Date: Sun, 27 Oct 2013 22:46:34 +0200 (IST)
From: Itay Furman <it...@nospammail.net>
To: Discussion list for LON-CAPA users <lon-capa-users@mail.lon-capa.org>
Subject: Re: [LON-CAPA-users] Duplicated ids found

On Sun, 27 Oct 2013, Raymond Batchelor wrote:

It seems to me that the id="11" is used within the imported file (which 
imports yet another library file) and redundantly in the actual problem 
file to import the first library file.  I think you 'might' want to use an 
id other than "11" in your problem file, for the import.

I see.
I will make the changes and test them later, when the questions will not be 
in active use.

Thanks,
Itay


----- Original Message -----
From: "Itay Furman" <it...@nospammail.net>
To: lon-capa-users@mail.lon-capa.org
Sent: Sunday, 27 October, 2013 08:45:18
Subject: [LON-CAPA-users] Duplicated ids found

Hi,

This is problem a newbie question. But I didn't find information on
this. Sorry for that.

After publishing a problem I get the following error message:

[start]
ERROR: Duplicated ids found, problem will operate incorrectly.
Duplicated ids seen:
11
This error occurred while processing response 12 in part
[end]

I could find in my code only a single id="11".
Note that the numerical ids in
  <import id="11">/res/jce/itayf/pub/lib/const_phys.library</import>
and
  <numericalresponse unit="C" format="2E" answer="$q" id="12">
were added by lon-capa after publication.

The code follows below.

Thanks in advance,
Itay

[start code]
<problem>
  <comment>
    File    = elec_coulomb_identical-hanging-charges.problem
    Author  = Itay Furman, PhD, it...@fastmail.fm
    Created = 2013-10-08
    Updated = 2013-10-08
    Version = 0.01

    Source  = Expanded from a problem by Michael Friedberg, JCE.
  </comment>

  <import id="11">/res/jce/itayf/pub/lib/const_phys.library</import>

  <script type="loncapa/perl">
    # Set-up

    $k_coulomb = $Coulomb_Const;
    $g      = 9.8;                                # Gravity acceleration [m 
/ s^2].
    $len    = &random(10, 50, 5);             # String length [cm].
    $theta  = &random(4,25,1);                    # Angle between string 
and vertical [degrees].
    $th_rad = $theta* $Pi / 180;                  # Same angle [rad].
    $mass   = &random(5,80,5);                    # Body mass [g].

    # Compute the magnitude of the charge on each body.
    $q = 2 * ($len/100) * sin($th_rad) * sqrt(($mass/1000) * $g * 
tan($th_rad) / $k_coulomb);
    # Note the following factors are required:
    # 1/100   in ($len/100)       to convert        $len: [cm]  -> [m].
    # 1/1000  in ($mass/1000)     to convert       $mass: [g]   -> [kg].
    # $Pi/180 in ($theta*$Pi/180) to convert sin()'s arg: [deg] -> [Rad].
  </script>

  <startouttext />
  <h2>The Electrostatic Force Between a Pair of Identical Hanging Point 
Charges</h2>

  <p>
    Two point bodies, each having a mass of <num>$mass</num> [g], are 
connected to identical massless
    isolating strings whose length is <num>$len</num> [cm].
    The strings are connected to the same hook on the ceiling.
  </p>
  <p>
    The bodies carry identical charges.
    Therefore, due to electrostatic repulsion, each string is inclined with 
an angle of
    $theta<sup>o</sup> relative to the line that pass through the hook and 
is orthogonal to the
    ceiling.
  </p>
  <endouttext />

  <part id="q" display="Compute the charge.">
    <startouttext />
    <strong>Compute: </strong> the electric charge on each body is
    <endouttext />

    <numericalresponse unit="C" format="2E" answer="$q" id="12">
      <responseparam name="tol" type="tolerance" default="2%" 
description="Numerical Tolerance" />
      <textline readonly="no" />
    </numericalresponse>
  </part>

  <img alt="A pair of identical hanging charged masses."
src="/res/jce/itayf/pub/share/img/131012_pair-hanging-charges.jpg"
encrypturl="no" />
<allow
src="/res/jce/itayf/pub/share/img/131012_pair-hanging-charges.jpg" />
</problem>

[end code]
_______________________________________________
LON-CAPA-users mailing list
LON-CAPA-users@mail.lon-capa.org
http://mail.lon-capa.org/mailman/listinfo/lon-capa-users



_______________________________________________
LON-CAPA-users mailing list
LON-CAPA-users@mail.lon-capa.org
http://mail.lon-capa.org/mailman/listinfo/lon-capa-users