[reza2031]

Hello,

Somehow, I need to use the value of latestTime in my code.

More explanation: I have set the stratTime to latestTime in controlDict.
In controlDict:

startTime latestTime;

I know that OpenFOAM calculates the latest written time in case directory automatically. Let's say the latest time folder is 10, how can I get the value 10 in the code?


Bests,
Reza

[Tobi]

Hi,

so in order to get the fields from the latest time step (as real time or incremental), you have to store them such as:

T.storeOldTime();

// To get the old time

T.oldTime()

However, this works if you are within a run. If you start your calculation at t=10s, you do not have access to the last time step (lets say 9.8s - if dt = 0.2). There is no functionality in FOAM because it does not make sense. E.g. generally, dt is not the same as writeTime.

[reza2031]

Thank you Tobi for the reply but it is not I was looking for. I am going to explain more. In my solver, I have these lines:

scalar eTime( readScalar(runTime.controlDict().lookup("endTime"))/nPoints );
scalar staTime( readScalar(runTime.controlDict().lookup("startTime")));

When the start time is 0 or when it's a scalar, everything is just fine. But, I am looking for a way to deal with "latestTime" in controlDict. OpenFOAM, somehow calculates the latest found directory in the case folder.
I checked Time.C and found this part:

{                               
    controlDict_.lookup("startTime") >> startTime_;                           
}                           
else                           
{                               
    // Search directory for valid time directories                               
    instantList timeDirs = findTimes(path(), constant());                        
                             
    if (startFrom == "firstTime")                               
    {                                   
        if (timeDirs.size())                                   
        {                                       
             if (timeDirs[0].name() == constant() && timeDirs.size() >= 2)
             {                                           
                   startTime_ = timeDirs[1].value();                                       
             }                                       
             else                                       
             {                                           
                   startTime_ = timeDirs[0].value();                                       
             }                                   
         }                               
    }                               
    else if (startFrom == "latestTime")                               
    {                                   
         if (timeDirs.size())                                   
         {                                       
               startTime_ = timeDirs.last().value();                                   
         }                               
    }
 }

OpenFOAM must save this "latest time" as a scalar. So, there should be a way to read the latest time as a scalar.




Reza

[Tobi]

You want to read the time value? I still did not get your point.
Getting the time value of the "latest Time" is explained in the code you wrote:

latestTime = timeDirs.last().value()

[reza2031]

That piece of code is from Time.C (source code for time)
https://github.com/OpenFOAM/OpenFOAM...db/Time/Time.C

I can write the below line in my code (It's a solver based on pisoFoam):

scalar latestTime = timeDirs.last().value();

I will get the error of declaration :

error: ‘timeDirs’ was not declared in this scope

Even if I include Time.H, it the same error.
So, how can I use this part of the Time.C and use it in my code?
I want to continue a case from a previous state. The problem is that I use the startTime as a scalar in my code to do some some calculation.So I need to change the startTime every time I want to resume a case from a previous time.

I am looking to do it automatically, writing latestTime in controlDict but my code should somehow reads the latesTime as a scalar, otherwise I get this error:

--> FOAM FATAL IO ERROR: 
wrong token type - expected Scalar, found on line 22 the word 'LatestTime'

Which is obvious as I have this line in my code:

scalar staTime( readScalar(runTime.controlDict().lookup("startTime")));

Any idea?


Reza

[Tobi]

Got it now. Yes it should be possible. The problem you have is related to the fact, that you do not have the object timeDir in your code. You should have access to that object via runTime.whateverFunction(); to get the function, doxygen is the proper way to look at.

[randolph]

db().time().startTime().value()

[lny200912]

Hi, Reza

Did you solve this problem? I also want to know how to get the value of latestTime in the controlDict as one scalar in the main programming?


Best regards,
Ningyi

[Michael@UW]

Originally Posted by reza2031

That piece of code is from Time.C (source code for time)
https://github.com/OpenFOAM/OpenFOAM...db/Time/Time.C

I can write the below line in my code (It's a solver based on pisoFoam):

scalar latestTime = timeDirs.last().value();

I will get the error of declaration :

error: ‘timeDirs’ was not declared in this scope

Even if I include Time.H, it the same error.
So, how can I use this part of the Time.C and use it in my code?
I want to continue a case from a previous state. The problem is that I use the startTime as a scalar in my code to do some some calculation.So I need to change the startTime every time I want to resume a case from a previous time.

I am looking to do it automatically, writing latestTime in controlDict but my code should somehow reads the latesTime as a scalar, otherwise I get this error:

--> FOAM FATAL IO ERROR: 
wrong token type - expected Scalar, found on line 22 the word 'LatestTime'

Which is obvious as I have this line in my code:

scalar staTime( readScalar(runTime.controlDict().lookup("startTime")));

Any idea?


Reza

Can you just add the line to access timeDirs?

instantList timeDirs = findTimes(path(), constant());

scalar latestTime = timeDirs.last().value();

latestTime is just a word for the if else control.

[otaolafr]

hello, not sure if the correct place to ask, I am looking to copy the last folder time from my case to use it as the 0 folder in the next (it is a two-step case)where the first I calculate the steady-state velocity and pressure fields and in the second doing a scalarTransport in transient so I can measure the RTD (residence time distribution) of steady-state flow in micromixer.
so I want to use simpleFoam to simulate the flow and when the residuals are low enought (from the residualControl in fvSoluion) copy the "lastTime folder" and renamed to a second case folder where I will do a scalarTransport.
but as the lastTime is controlled by the residualControl I not going to be able to know from the beginning of the simulation when it is going to be converged.

best regards,
franco

[randolph]

Franco,

I think you have two solutions:

1. just simply use the bash command with some regular expression to copy the last time step folder to your new case.

2. use the mapFields with sourceTime option to map the solution from the flow solution to your new case.

Thanks,
Rdf

[Tobi]

Hi all, I guess the first option is sufficient as the mesh should be the same.

Tobi

[otaolafr]

Originally Posted by randolph

Franco,

I think you have two solutions:

1. just simply use the bash command with some regular expression to copy the last time step folder to your new case.

2. use the mapFields with sourceTime option to map the solution from the flow solution to your new case.

Thanks,
Rdf

hi randolph, and tobi
thanks for the answers, yes as tobi said, i think the first option is better as it is going to be exactly the same mesh, but my issue is how to setup a command to do it (as i wanted to integrated in an Allrun file) sorry as linux is new to me i am learning at the same time:
i wanted to have this structure of folder:
Simulation
------AllrunSimulation
+----sim1
---------+----0
---------+----lastTime
---------+----constant
---------+----system
----------Allrunsim1
----------Allclean
+----sim2
---------+----constant
---------+----system
----------Allrunsim2
----------Allclean
and for my AllrunSimulation file have a code like this:

cd ./sim1
./Allclean
./Allrunsim1
cd ..
./sim2/Allclean
cp -r ./sim1/lastTime ./sim2/0
./sim2/Allrunsim2

my issue is that i dont know how to "select" the lastTime automatically.. (what i think you mean by the option 1)..
thanks for the help,
franco

[Tobi]

You want to start the first guy and after it finish, the second calculation should start automatically?

[otaolafr]

Originally Posted by Tobi

You want to start the first guy and after it finish, the second calculation should start automatically?

is what i wanted to do at least....
run first case,
when finish copy the last folder to the second case (as 0 folder)
and run the second case.

as my idea is to leave it running during the nights, it would be my "ideal" case so it does not need intervention in middle of it.
franco

[Tobi]

What about some bash magic?

ls -1 | sort -n | tail -n 1

Tobi

[otaolafr]

Originally Posted by Tobi

What about some bash magic?

ls -1 | sort -n | tail -n 1

Tobi

Looool literally magic 😂😂😂 thanks to bother helping newbies like me, 🙂 I will have a look to understand it

[randolph]

Franco,

If you want go with the second solution, you can run this command in your transport case folder

mapFields <origional case with flow solution> -sourceTime latestTime -consistent

The argument latestTime will automatically parse the latest solution in that folder.

Thank,
Rdf

[otaolafr]

Originally Posted by randolph

Franco,

If you want go with the second solution, you can run this command in your transport case folder

mapFields <origional case with flow solution> -sourceTime latestTime -consistent

The argument latestTime will automatically parse the latest solution in that folder.

Thank,
Rdf

thanks rdf! in case that i need a thinner mesh for the second case it will be a good solution, thanks a lot man

Originally Posted by Tobi

What about some bash magic?

ls -1 | sort -n | tail -n 1

Tobi

hello tobi, sorry to bother you, but when i do this in the bash it works correctly but when i do it from an allrun file it begings coping...; i think the Ubuntu subsystem? not sure... (but at least a lot of files... and not the correct ones...)

#!/bin/sh
cd ${0%/*} || exit 1 # Run from this directory

lastestTime=ls -1 | sort -n | tail -n 1;
cp -r $lastestTime/. ./testFolder/

directly in the terminal ls -1 | sort -n | tail -n 1 gives the correct answer but not from the allrun test.
any idea? thanks.

hello, i just came back to give an answer to my problem, for anyone that could need it and also so no one waste time in answering it
:credits to https://unix.stackexchange.com/quest...shell-variable

to stock the correct output the syntaxis is

lastestTime=$(ls -1 | sort -n | tail -n 1);

also works:

lastestTime=$( bash <<EOF
ls -1
sort -n
tail -n 1
EOF
)

and to use it as a folder name for the cp command,

cp -r "$lasT" ./testFolder/

best regards!