Can a parameter be used to set the unit attribute for a component? - runtime-error

So far, using Wolfram System Modeler 4.3 and 5.1 the following minimal example would compile without errors:
model UnitErrorModel
MyComponent c( hasUnit = "myUnit" );
block MyComponent
parameter String hasUnit = "1";
output Real y( unit = hasUnit );
equation
y = 10;
end MyComponent;
end UnitErrorModel;
But with the new release of WSM 12.0 (the jump in version is due to an alignment with the current release of Wolfram's flagship Mathematica) I am getting an error message:
Internal error: Codegen.getValueString: Non-constant expression:c.hasUnit
(Note: The error is given by WSMLink'WSMSimulate in Mathematica 12.0 which is running System Modeler 12.0 internally; here asking for the "InternalValues" property of the above model since I have not installed WSM 12.0 right now).
Trying to simulate the above model in OpenModelica [OMEdit v. 1.13.2 (64-bit)] reveals:
SimCodeUtil.mo: 8492:9-8492:218]: Internal error Unexpected expression (should have been handled earlier, probably in the front-end. Unit/displayUnit expression is not a string literal: c.hasUnit
So it seems that to set the unit attribute I cannot make use of a variable that has parameter variability? Why is this - after all shouldn't it suffice that the compiler can hard-wire the unit when compiling for runtime (after all the given model will run without any error in WSM 4.3 and 5.1)?
EDIT: From the answer to an older question of mine I had believed that at least final parameters might be used to set the unit-attribute. Making the modification final (e.g. c( final hasUnit = "myUnit" ) does not resolve the issue.

I have been given feedback on Wolfram Community by someone from Wolfram MathCore regarding this issue:
You are correct in that it's not in violation with the specification,
although making it a constant makes more sense since you would
invalidate all your static unit checking if you are allowed to change
the unit after building the simulation. We filed an issue on the
specification regarding this (Modelica Specification Issue # 2362).
So, MatheCore is a bit ahead of the game in proposing a Modelica specification change that they have already implemented. ;-)
Note: That in Wolfram System Modeler (12.0) using the annotation Evaluate = true will not cure the problem (cf. the comment above by #matth).
As a workaround variables used to set the unit attribute should have constant variability, but can nevertheless by included in user dialogs to be interactively changed using annotation(Dialog(group = "GroupName")).

Related

How to avoid RuntimeError while call __dict__ on module?

it is appearing in some big modules like matplotlib. For example expression :
import importlib
obj = importlib.import_module('matplotlib')
obj_entries = obj.__dict__
Between runs len of obj_entries can vary. From 108 to 157 (expected) entries. Especially pyplot can be ignored like some another submodules.
it can work stable during manual debug mode with len computing statement after dict extraction. But in auto it dont work well.
such error occures:
RuntimeError: dictionary changed size during iteration
python-BaseException
using clear python 3.10 on windows. Version swap change nothing at all
during some attempts some interesting features was found.
use of repr is helpfull before dict initiation.
But if module transported between classes like variable more likely lazy-import happening? For now there is evidence that not all names showing when command line interpriter doing opposite - returning what expected. So this junk of code help bypass this bechavior...
Note: using pkgutil.iter_modules(some_path) to observe modules im internal for pkgutil ModuleInfo form.
import pkgutil, importlib
module_info : pkgutil.ModuleInfo
name = module_info.name
founder = module_info.module_finder
spec = founder.find_spec(name)
module_obj = importlib.util.module_from_spec(spec)
loader = module_obj.__loader__
loader.exec_module(module_obj)
still unfamilliar with interior of import mechanics so it will be helpfull to recive some links to more detail explanation (spot on)

How can I change a CPLEX parameter in my Julia code?

I'm using the CPLEX solver to run my ILP model.The ILP model is implemented with Julia/MultiJuMP.
I would like to limit the time of optimization of the problem. If I were working with OPL, I would just have to add Cplex.tilimt=100
In Julia, I put the following code :
mmodel = MultiModel(solver = CplexSolver("CPLEX.tilim"=100), linear = true)
It doesn't work.
From the last section in https://github.com/JuliaOpt/CPLEX.jl/blob/master/README.md, it appears that Julia uses the legacy parameter names as they appear in the C API of CPLEX. For example, CplexSolver(CPX_PARAM_EPINT=1e-8).
Here's the link to the the CPLEX documentation for that parameter: https://www.ibm.com/support/knowledgecenter/SSSA5P_12.9.0/ilog.odms.cplex.help/CPLEX/Parameters/topics/EpInt.html. As you can see, the name appears as the first row in the 'Name prior to V12.6.0' column.
For the time limit, you should thus use CPX_PARAM_TILIM, as this is the name in https://www.ibm.com/support/knowledgecenter/SSSA5P_12.9.0/ilog.odms.cplex.help/CPLEX/Parameters/topics/TiLim.html.

First token could not be read or is not the keyword 'FoamFile' in OpenFOAM

I am a beginner to programming. I am trying to run a simulation of a combustion chamber using reactingFoam.
I have modified the counterflow2D tutorial.
For those who maybe don't know OpenFOAM, it is a programme built in C++ but it does not require C++ programming, just well-defining the variables in the files needed.
In one of my first tries I have made a very simple model but since I wanted to check it very well I set it to 60 seconds with a 1e-6 timestep.
My computer is not very powerful so it took me for a day aprox. (by this I mean I'd like to find a solution rather than repeating the simulation).
I executed the solver reactingFOAM using 4 processors in parallel using
mpirun -np 4 reactingFOAM -parallel > log
The log does not show any evidence of error.
The problem is that when I use reconstructPar it works perfectly but then I try to watch the results with paraFoam and this error is shown:
From function bool Foam::IOobject::readHeader(Foam::Istream&)
in file db/IOobject/IOobjectReadHeader.C at line 88
Reading "mypath/constant/reactions" at line 1
First token could not be read or is not the keyword 'FoamFile'
I have read that maybe some files are empty when they are not supposed to be so, but I have not found that problem.
My 'reactions' file have not been modified from the tutorial and has always worked.
edit:
Sorry for the vague question. I have modified it a bit.
A typical OpenFOAM dictionary file always contains a Foam::Istream named FoamFile. An example from a typical system/controlDict file can be seen below:
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object controlDict;
}
During the construction of the dictionary header, if this Istream is absent, OpenFOAM ceases its operation by raising an error message that you have experienced:
First token could not be read or is not the keyword 'FoamFile'
The benefit of the header is possibly to contribute OpenFOAM's abstraction mechanisms, which would be difficult otherwise.
As mentioned in the comments, adding the header entity almost always solves this problem.

Qt error is printed on the console; how to see where it originates from?

I'm getting this on the console in a QML app:
QFont::setPointSizeF: Point size <= 0 (0.000000), must be greater than 0
The app is not crashing so I can't use the debugger to get a backtrace for the exception. How do I see where the error originates from?
If you know the function the warning occurs in (in this case, QFont::setPointSizeF()), you can put a breakpoint there. Following the stack trace will lead you to the code that calls that function.
If the warning doesn't include the name of the function and you have the source code available, use git grep with part of the warning to get an idea of where it comes from. This approach can be a bit of trial and error, as the code may span more than one line, etc, and so you might have to try different parts of the string.
If the warning doesn't include the name of the function, you don't have the source code available and/or you don't like the previous approach, use the QT_MESSAGE_PATTERN environment variable:
QT_MESSAGE_PATTERN="%{function}: %{message}"
For the full list of variables at your disposal, see the qSetMessagePattern() docs:
%{appname} - QCoreApplication::applicationName()
%{category} - Logging category
%{file} - Path to source file
%{function} - Function
%{line} - Line in source file
%{message} - The actual message
%{pid} - QCoreApplication::applicationPid()
%{threadid} - The system-wide ID of current thread (if it can be obtained)
%{qthreadptr} - A pointer to the current QThread (result of QThread::currentThread())
%{type} - "debug", "warning", "critical" or "fatal"
%{time process} - time of the message, in seconds since the process started (the token "process" is literal)
%{time boot} - the time of the message, in seconds since the system boot if that can be determined (the token "boot" is literal). If the time since boot could not be obtained, the output is indeterminate (see QElapsedTimer::msecsSinceReference()).
%{time [format]} - system time when the message occurred, formatted by passing the format to QDateTime::toString(). If the format is not specified, the format of Qt::ISODate is used.
%{backtrace [depth=N] [separator="..."]} - A backtrace with the number of frames specified by the optional depth parameter (defaults to 5), and separated by the optional separator parameter (defaults to "|"). This expansion is available only on some platforms (currently only platfoms using glibc). Names are only known for exported functions. If you want to see the name of every function in your application, use QMAKE_LFLAGS += -rdynamic. When reading backtraces, take into account that frames might be missing due to inlining or tail call optimization.
On an unrelated note, the %{time [format]} placeholder is quite useful to quickly "profile" code by qDebug()ing before and after it.
I think you can use qInstallMessageHandler (Qt5) or qInstallMsgHandler (Qt4) to specify a callback which will intercept all qDebug() / qInfo() / etc. messages (example code is in the link). Then you can just add a breakpoint in this callback function and get a nice callstack.
Aside from the obvious, searching your code for calls to setPointSize[F], you can try the following depending on your environment (which you didn't disclose):
If you have the debugging symbols of the Qt libs installed and are using a decent debugger, you can set a conditional breakpoint on the first line in QFont::setPointSizeF() with the condition set to pointSize <= 0. Even if conditional breakpoints don't work you should still be able to set one and step through every call until you've found the culprit.
On Linux there's the tool ltrace which displays all calls of a binary into shared libs, and I suppose there's something similar in the M$ VS toolbox. You can grep the output for calls to setPointSize directly, but of course this won't work for calls within the lib itself (which I guess could be the case when it handles the QML internally).

TensorFlow: Can't invoke streaming_sparse_precision_at_k

Upon trying to calculate precision#k, I get an exception. To what follows is the a simple code that reproduces the problem.
First the code defines the variable scope:
initializer = tf.random_uniform_initializer(-0.1, 0.1, seed=1234)
with tf.variable_scope("model", reuse=None, initializer=initializer)
Then it calls those lines:
predictions = tf.Variable(tf.ones([2, 10], tf.int64))
labels = tf.Variable(tf.ones([2, 1], tf.int64))
precision = tf.contrib.metrics.streaming_sparse_precision_at_k(predictions, labels, 5)
tf.initialize_all_variables().run()
(I know this code is meaningless, and tries to calculate the precision given 2 fixed matrices...)
Then I get the following exception:
W tensorflow/core/framework/op_kernel.cc:936] Failed precondition:
Attempting to use uninitialized value
model/precision_at_5/false_positive_at_5 [[Node:
model/precision_at_5/false_positive_at_5/read = IdentityT=DT_DOUBLE,
_class=["loc:#model/precision_at_5/false_positive_at_5"], _device="/job:localhost/replica:0/task:0/gpu:0"]]
The same goes when I tried to invoke streaming_sparse_recall_at_k instead of streaming_sparse_precision_at_k.
The installed version is r0.10 on linux with python 2.7.
Please help... Thanks in advance :)
Unfortunately, tf.initialize_all_variables() doesn't initialize "local" variables (which tend to be internal implementation details for ops like tf.contrib.metrics.streaming_sparse_precision_at_k() and tf.train.string_input_producer(), as opposed to variables used as model weights).
You'll need to add a line to your program that runs tf.initialize_local_variables() before running the evaluation op:
sess.run(tf.initialize_local_variables()) # or `tf.initialize_local_variables().run()`

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