i'm noob for modelica and developing the Heat Exchanger model.
I did input
air_in.X_outflow[1]=1;
air_out.X_outflowp[1]=1;
coolant_in.X_outflow[1]=1;
coolant_out.X_outflow[1]=1;
but I encountered some errors like captures below.
First, I don't know what is the physical meaning of C_outflow. I could find that C_outflow = c_i/m
and m is the mass of the fluid, but couldn't find the meaning of c_i.
Second, I've just tried to input the value 0~1 as the description said, but encountered the error message above. I think the value has not been input to the C_outflow array but I'm not sure.
Please reply to anyone who can figure out these problems... Thank you to all of you.
model Staggered_HX
A complete model would be helpful - but attempting to answer anyway:
The C-array is an array of trace substances, and there are normally no trace substances; whereas the X-array is the array of normal substances - which must contain some elements.
For the C-array it would thus be: air_in.C_outflow=zeros(0); (where zeros(0) creates an empty vector - corresponding to no trace substabces), but I don't see how that relates to the equations above with air_in.X_outflow[1]=1;
Related
I´m trying to set a connection with a conditional on the temperature, to represent a temperature-sensible charging pipe that works inside a stratified heat storage tank, with the following for loop reading the several volumes of the tank,
`for i in 2:nSeg loop
if (sensor_T_inflow.T > vol[i].T) and (sensor_T_inflow.T < vol[i-1].T) then
connect(feedPort, vol[i].ports[3])
annotation (Line(points={{-50,-60},{6,-60},{6,
-16},{16,-16}}, color={0,127,255}));
end if;
end for;`
However I get the errors such as this one for the volume 2:
Failed to expand block containing connect:
if (sensor_T_inflow.T > vol[2].T and sensor_T_inflow.T < vol[1].T) then connect(feedPort, vol[2].ports[3]); end if;
The model contained invalid connect statements.
Check aborted.
This might have a silly solution but I checked the names of all my elements and their temperature properties and they match with this code snippet, and I confirmed the error comes specially from the if conditional. Here is my model If you could take a look at it.
I tried commenting out the conditional and the check was succesful, only that I have a misbalance of about 40 variables to equations. If you got any advice on how to solve those misbalances I´d be much grateful as well.
Thanks a lot in advance.
The connect-statements may not depend on time-varying variables.
(The technical statement is first in the list in https://specification.modelica.org/master/connectors-and-connections.html#restrictions-of-connections-and-connectors )
A solution would be to turn that into an array of valve-components, and have them controlled in a similar way.
I'm just starting out with thMap.
So far I have successfully mapped an X12 835 message to output structures. That works no problem.
I have also successfully acquired the LoopIndex of the current loop using the LoopIndex() function.
My challenge:
I need to get the value of an element from the enclosing loop.
In the attached image, everything in green is working.
I'm trying to get the value down the red line.
My goal is to do this assignment
gsRecord.parent_id = enclosing loop isaRecord.id
The documentation explains some things but I don't see examples putting it together.
Does anyone have any good examples, videos or suggestions?
Update from 12/9/22
Here is something I have tried. Providing this example in hopes someone recognizes a specific issue to help move me forward. Any input would be appreciated.
Per this screenshot
I am attempting to output in gsRecord.parent_id the loopIndex of the parent loop (isaRecord).
This gives me the following error
"An reference in an LoopIndex/Variable was made to an either an input
map element or an output map element that is not in the context of the
reference. Use an enclosing looping output map element here.(msg #1202)"
Given the reference to 'enclosing looping output map element here' it feels like the gsRecord is not properly defined as a child of the isaRecord.
However the definition of the gsRecord is in reference to the isaRecord as in this screenshot.
It feels like there is some combination of LoopIndex and EnclosedContext that I could use to accomplish this but I'm unable to find any in-depth documentation on the functions.
Any help would be appreciated.
I am using clingo to solve a homework problem and stumbled upon something I can't explain:
normalized(0,0).
normalized(A,1) :-
A != 0.
normalized(10).
In my opinion, normalized should be 0 when the first parameter is 0 or 1 in every other case.
Running clingo on that, however, produces the following:
test.pl:2:1-3:12: error: unsafe variables in:
normalized(A,1):-[#inc_base];A!=0.
test.pl:2:12-13: note: 'A' is unsafe
Why is A unsafe here?
According to Programming with CLINGO
Some error messages say that the program
has “unsafe variables.” Such a message usually indicates that the head of one of
the rules includes a variable that does not occur in its body; stable models of such
programs may be infinite.
But in this example A is present in the body.
Will clingo produce an infinite set consisting of answers for all numbers here?
I tried adding number(_) around the first parameter and pattern matching on it to avoid this situation but with the same result:
normalized(number(0),0).
normalized(A,1) :-
A=number(B),
B != 0.
normalized(number(10)).
How would I write normalized properly?
With "variables occuring in the body" actually means in a positive literal in the body. I can recommend the official guide: https://github.com/potassco/guide/releases/
The second thing, ASP is not prolog. Your rules get grounded, i.e. each first order variable is replaced with its domain. In your case A has no domain.
What would be the expected outcome of your program ?
normalized(12351,1).
normalized(my_mom,1).
would all be valid replacements for A so you create an infinite program. This is why 'A' has to be bounded by a domain. For example:
dom(a). dom(b). dom(c). dom(100).
normalized(0,0).
normalized(A,1) :- dom(A).
would produce
normalize(0,0).
normalize(a,1).
normalize(b,1).
normalize(c,1).
normalize(100,1).
Also note that there is no such thing as number/1. ASP is a typefree language.
Also,
normalized(10).
is a different predicate with only one parameter, I do not know how this will fit in your program.
Maybe your are looking for something like this:
dom(1..100).
normalize(0,0).
normalize(X,1) :- dom(X).
foo(43).
bar(Y) :- normalize(X,Y), foo(X).
I've got the error of "Error using histc. First Input must be a real non-sparse numeric array" from the following codes.
N=10^4;
d=rand(1,N)>0.5;
symbols=unique(d);
probs = histc(d,symbols)./numel(d);
P/s: I try to generate using randsrc before. It did worked.But, I'm hoping not to use randsrc because it will affect my code later on. Any ideas on this would be appreciated.
Thanks.
Here is the working code
N=10^4;
d=double(rand(1,N)>0.5);
symbols=unique(d);
probs = histc(d,symbols)./numel(d);
I need to categorize a dataset according to different age groups. The categorization depends on whether the Sex is Male or Female. I first subset the data by gender and then use the ordinal function (dataset is from a Matlab example). The following code crashes on the last line when I try to vertically concatenate the subsets:
load hospital;
subset_m=hospital(hospital.Sex=='Male',:);
subset_f=hospital(hospital.Sex=='Female',:);
edges_f=[0 20 max(subset_f.Age)];
edges_m=[0 30 max(subset_m.Age)];
labels_m = {'0-19','20+'};
labels_f = {'0-29','30+'};
subset_m.AgeGroup= ordinal(subset_m.Age,labels_m,[],edges_m);
subset_f.AgeGroup = ordinal(subset_f.Age,labels_f,[],edges_f);
vertcat(subset_m,subset_f);
Error using dataset/vertcat (line 76)
Could not concatenate the dataset variable 'AgeGroup' using VERTCAT.
Caused by:
Error using ordinal/vertcat (line 36)
Ordinal levels and their ordering must be identical.
Edit
It seems that a vital part was missing in the question, here is the answer to the corrected question. You need to use join rather than vertcat, for example:
joinFull = join(subset_f,subset_m,'LeftKeys','LastName','RightKeys','LastName','type','rightouter','mergekeys',true)
Solution of original problem
It seems like you are actually trying to work with the wrong variable. If I change all instances of hospitalCopy into hospital then everything works fine for me.
Perhaps you copied hospital and edited it, thus losing the validity of the input.
If you really need to have hospitalCopy make sure to assign to it directly after load hospital.
If this does not help, try using clear all before running the code and make sure there is no file called 'hospital' in your current directory.