VMD terminates simulation before completion - simulation

I am trying to run a 1 ns simulation using VMD/NAMD on top of my 200 ps simulation, so I set the program to run 800000 with a timestep of 1. However, the next day (it took about 12 hours) it was complete, but I only had ~16500 frames. Anyone know why the program only collected so many frames? I have a similar issue with running different simulations: the amount I ask it to run and the number of frames I get are not the same.

Related

Internal multithread error during variation experiment

I run a parameter variation experiment that varies five parameters of two levels each to yield 32 iterations. During the run, the error in the attached image occurred.
-When running this design three separated times with no replications in any of them, the error occurred only in one run of the three.
-When adding replications to the run (even as few as two replications) the error always occurs too early in run time.
-My selection for the maximum available memory for the experiment is: 60,000 Mb of the total 46Gb RAM of the device
-Disabling of parallel execution doesn't seem appealing due to the consequent slow run speed; I use material handling library, and it takes around 18 minutes for a single day run time.
How can I overcome this error?
Thanks

Labview FPGA Simulation Timing

This is a very basic question. I can't simulate a PWM file, in system time, from its FPGA VI file.
Details
For a NI cRIO-9067 + LabVIEW 2016 + Windows 8 system, under FPGA Interface Mode, I have the Test VI No.1.vi NI LabVIEW file and the corresponding FPGA Desktop Execution Node block file Test VI No.1 DEN.vi as suggested in the Getting Started information [1] [2].
In both files, the Low Pulse and High Pulse Numeric Controls are filled with the 1000 value. The Loop Timer block is set as "mSec" Counter Unit and "32 Bit" Size of Internal Counter.
The compiled FPGA version of the first file executes a square wave changing each 1 second, as expected, after 7 minutes of local compilation.
Under Simulation (Simulated I/O) as Execution Mode, and for reproducing approximatedly and by trial and error the square wave timing every 1 second, I need to put the value 1750 in the Clock Ticks field, from the FPGA 40MHz Onboard Clock reference clock, shown in the block options.
I dont understand this block, and why i should not put any close divisor of 40,000,000 at the Clock Ticks field, or simply, the value 1. Basically i dont understand how to "time" these FPGA simulations.
The desktop execution node is designed for time based simulation you are definately on the right track.
What you are setting at the top is the number of cycles that are executed each time you call the node. In your case you have 1750 ticks so around 43.75us of simulated time per iteration.
To simulate in real time you need to make sure that you execute the same amount of simulated time as the simulation loop takes to run. In your case, you have no timing in your simulation loop so why 1750 works for you is because that is probably how long that loop takes to execute.
If you put a loop timer in of 1ms and set the clock ticks to 40,000 (1ms simulated time) then I think you will find that it also works.
In some cases it may be beneficial to execute faster than real time so you would just have to account for that in your maths. For example if you set the clock ticks to 40 (1us simulated time) then you can count the number of iterations and multiply by 1us to get the actual clock time.

Matlab: run program until condition is met

I'm currently modelling the dynamics of an ice sheet. I therefore made a script that plots the volume of an ice sheet throughout time (in steps of 500 years). The volume increases rapidly at first, but the curve flattens later on as the volume does not change anymore and the ice sheet is in steady state... its shape is familiar like y=ln(x)... I thus have 2 output arrays, namely a) vol_time with the time in steps of 500 years and b) vol with the corresponding volume. Now, the program runs until a fixed time that I inserted (200 000 years) but I want to run the program only until this steady state is reached. So my question is: how can I make the program run only until the volume changes with only 0.002% per 500 years?
Thanks
You can ether wrap your ice-sheet thickness calculation in a while loop so the code performs the calculation until the 0.0002% condition is met or you loop through the whole 200.000 years.
Another option could be to add a if check end the end of your ice-sheet thickness calculation and if you enter and then add break in the if, this way the loop terminate.

Reach to the required ticks of the simulation

Dear Netlogo community,
I have created a simulation enviornment on Netlogo, which runs around 35000 ticks. It takes around 70 to 80 mins to execute completely. I am facing some errors at the end of simulation (near 25000 ticks). Now I am debugging program by using print command. simulation takes 45 to 50 mins to reach to the desired tick (a ticks that creates problem). Is there any fast way in Netlogo by using which i can reach to the desired tick quickly.
As JenB suggests, use the export-world and import-world primitives to save and restore world state. Or use the equivalent menu items of the same names on NetLogo's File menu.

matlab script node in Labview with different timing

I have a DAQ for Temperature measurment. I take a continuous sample rate and after DAQ, calculating temperature difference per minute (Cooling Rate: CR) during this process. This CR and temperature values are inserted into the Matlab script for a physical model running (predicting the temperature drop for next 30 sec). Then, I record and compare the predicted and experimental values in LabVIEW.
What i am trying to do is the matlab model is executing every 30 sec, and send out its predictions as an output from matlab script. One of this outputs helps me to change the Air Blower Motor Speed until next matlab run( eventually affect the temperature drop for next 30 sec as well, which becomes a closed loop). After 30 sec while main process is still running, sending CR and temperature values to matlab model again, and so on.
I have a case structure for this Matlab script. And inside of case structure i applied an elapsed time function to control the timing for the matlab script, but this is not working.
Yes. Short answer: I believe (one of) the reasons the program behaves weird on changed timing are several race conditions present in the code.
The part of the diagram presented shows several big problems with the code:
Local variables lead to race conditions. Use dataflow. E.g. you are writing to Tinitial local variable, and reading from Tinitial local varaible in the chunk of code with no data dependencies. It is not known whether reading or writing will happen first. It may not manifest itself badly with small delays, while big delays may be an issue. Solution: rewrite you program using the following example:
From Bad:
To Good:
(nevermind broken wires)
Matlab script node executes in the main UI execution system. If it is executing for a long time, it may freeze indicators/controls as well as execution of other pieces of code. Change execution system of other VIs in your program (say to "other 1") and see if the situation improves.