Search found 148 matches
- Sat May 04, 2019 4:20 pm
- Forum: Vensim
- Topic: demand and supply at price
- Replies: 29
- Views: 12742
Re: demand and supply at price
Yes, that kind of thing can be done. You can also use FIND ZERO for a more general solution to simultaneous problems. There's a sample model for each included in the Help system. Thank you. I modelled it with ALLOCATE AVAILABLE function. But still I want to know how to define priority dynamicly tha...
- Fri May 03, 2019 2:50 pm
- Forum: Vensim
- Topic: demand and supply at price
- Replies: 29
- Views: 12742
Re: demand and supply at price
Hi, I would like to ask a question which is related to this post. I want to do dispatch of power plants with Vensim itself. Assume that I have 3 power plants with specific price(a1,a2,a3) and capacity(b1,b2,b3). They take part in one auction for satisfying the demand(D). Power plants will be sorted ...
- Fri Apr 26, 2019 3:20 pm
- Forum: Vensim
- Topic: How to count number of storage cycle
- Replies: 2
- Views: 1684
Re: How to count number of storage cycle
The word "count" implies "stock". You can do something like the following: count = INTEG( counting, 0 ) counting = start of cycle/TIME STEP start of cycle = {logical flag - a function of your process} The trick is to avoid counting the same cycle in consecutive TIME STEPS, but i...
- Thu Apr 25, 2019 2:54 pm
- Forum: Vensim
- Topic: How to count number of storage cycle
- Replies: 2
- Views: 1684
How to count number of storage cycle
Hi,
I want to consider a maximum number of storage cycle for storage technology in my model. It means that a storage technology cannot exceed its maximum number of cycle. Do you have any suggestion how to model it in Venism.
*Whenever it is used it can be consider as a one cycle.
Best Regards
I want to consider a maximum number of storage cycle for storage technology in my model. It means that a storage technology cannot exceed its maximum number of cycle. Do you have any suggestion how to model it in Venism.
*Whenever it is used it can be consider as a one cycle.
Best Regards
- Wed Feb 27, 2019 12:25 pm
- Forum: Vensim
- Topic: Not enough memory error
- Replies: 9
- Views: 4236
Re: Not enough memory error
64 bit Vensim will have all the same functions as 32 bit Vensim. If you use external functions, you will need to re-compile these to create a 64 bit DLL before use. 64 bit version will not decrease running time (it will probably take longer to run). Do have any other suggestion for decreasing runni...
- Wed Feb 27, 2019 10:39 am
- Forum: Vensim
- Topic: Not enough memory error
- Replies: 9
- Views: 4236
Re: Not enough memory error
Wow - this is huge to run with such a fine time step - it's generating something like 200 billion floating point numbers. I think you probably need 64-bit, even with other strategies like using a savelist to reduce storage. What is this about? I have increased size of the model by adding more power...
- Wed Feb 20, 2019 4:48 pm
- Forum: Vensim
- Topic: How to change external function
- Replies: 7
- Views: 3322
- Wed Feb 20, 2019 3:28 pm
- Forum: Vensim
- Topic: How to change external function
- Replies: 7
- Views: 3322
Re: How to change external function
Users\public\vensim\cfiles isn't part of the Vensim distribution - could you have received that from whoever wrote the code for the external function? Yes, your are right. This folder has been added to Vensim folder and I want to edit its external fucntion which are all in '.obj' format. Can I add ...
- Wed Feb 20, 2019 2:02 pm
- Forum: Vensim
- Topic: How to change external function
- Replies: 7
- Views: 3322
Re: How to change external function
What I have to clarify is that, I want to edit one of user defined functions. The thing is that, I do not find its C cource in COMP path(C:\Users\Public\Vensim\COMP) or cfiles path(C:\Users\Public\Vensim\cfiles), although I just see its .obj foramt in cfiles path.
- Wed Feb 20, 2019 10:55 am
- Forum: Vensim
- Topic: How to change external function
- Replies: 7
- Views: 3322
Re: How to change external function
Do you already have an external function library? I have one 'venext.lib' in this folder( C:\Users\Public\Vensim\cfiles). My model already has its own external function and it works well. I just want to know how can I edit one of these external functions. If yes, you must have edited the C code in ...
- Wed Feb 20, 2019 10:23 am
- Forum: Vensim
- Topic: How to change external function
- Replies: 7
- Views: 3322
How to change external function
Hi, As you know, the address of external function in Vensim is in C:\Users\Public\Vensim\cfiles\venext.dll. But in this folder all files are in machine code. I want to change some part of my external functions but I cannot access their C format in this folder? Do you know which file has to be change...
- Wed Feb 13, 2019 1:40 pm
- Forum: Vensim
- Topic: Limitation for number of characters in Subscripts
- Replies: 3
- Views: 2006
Re: Limitation for number of characters in Subscripts
Can you give an example of what you are doing? For example, I had 380 power plants in last version of my model but as I added more power plants to it, it has 1700 power plants now(i define this power plants in subscripts). The thing is that I cannot add more more power plants in subscripts becasue ...
- Wed Feb 13, 2019 1:17 pm
- Forum: Vensim
- Topic: Limitation for number of characters in Subscripts
- Replies: 3
- Views: 2006
Limitation for number of characters in Subscripts
Hi,
Does vensim have limitation for the number of characters in subscripts? When I wanted to add more characters in subscripts, I noticed that I cananot do it because it is impossible to add more than a fixed number of characters.
Do you have any suggestion for adding more characters?
Best Regards
Does vensim have limitation for the number of characters in subscripts? When I wanted to add more characters in subscripts, I noticed that I cananot do it because it is impossible to add more than a fixed number of characters.
Do you have any suggestion for adding more characters?
Best Regards
- Sat Jan 26, 2019 4:03 pm
- Forum: Vensim
- Topic: Text mode problem
- Replies: 9
- Views: 6174
Re: Text mode problem
I solved it. The problem was related to the compiler. Vensim had lost its connection to compiler, as a result, I could not change its text mode to sketch mode.Administrator wrote: ↑Sat Jan 26, 2019 3:40 pm It's hard to see anything on that image. What is "min cost flows"? And where does the cursor end up when you click ok?
- Sat Jan 26, 2019 3:24 pm
- Forum: Vensim
- Topic: Text mode problem
- Replies: 9
- Views: 6174
Re: Text mode problem
I get attached error. No I do save it in Dropbox/OneDrive/Google drive.Administrator wrote: ↑Sat Jan 26, 2019 3:19 pm Can you share the syntax error?
And do you save your models in Dropbox/OneDrive/Google drive?
- Sat Jan 26, 2019 3:08 pm
- Forum: Vensim
- Topic: Text mode problem
- Replies: 9
- Views: 6174
Text mode problem
Hi,
I closed my model yesterday without any problem, but when I want to open it today it is text mode. When I want to change its mode from text to sketch I get this error: "Syntax error". Can you help me how to fix this problem.
Best Regards
I closed my model yesterday without any problem, but when I want to open it today it is text mode. When I want to change its mode from text to sketch I get this error: "Syntax error". Can you help me how to fix this problem.
Best Regards
- Tue Jan 08, 2019 2:49 pm
- Forum: Vensim
- Topic: 64 bit beta release
- Replies: 21
- Views: 23033
Re: 64 bit beta release
Hi,
I have licence of DSS version(32 bit). How can I increase it to 64 bit?
Best Regards
I have licence of DSS version(32 bit). How can I increase it to 64 bit?
Best Regards
- Sun Jan 06, 2019 5:28 pm
- Forum: Vensim
- Topic: Not enough memory error
- Replies: 9
- Views: 4236
Re: Not enough memory error
Wow - this is huge to run with such a fine time step - it's generating something like 200 billion floating point numbers. I think you probably need 64-bit, even with other strategies like using a savelist to reduce storage. What is this about? I am using a savelist with 100 variables in its list. D...
- Sun Jan 06, 2019 1:10 pm
- Forum: Vensim
- Topic: Not enough memory error
- Replies: 9
- Views: 4236
- Sat Jan 05, 2019 4:48 pm
- Forum: Vensim
- Topic: Not enough memory error
- Replies: 9
- Views: 4236
Not enough memory error
Hi,
My model has 73249 time steps and when I run it, I get this error at different time steps:
"Not enough memory-decrease lenght or increase SAVEPER"
As it occures at different time steps I would like to ask you what is your suggestion for fixing it.
Best Regards,
My model has 73249 time steps and when I run it, I get this error at different time steps:
"Not enough memory-decrease lenght or increase SAVEPER"
As it occures at different time steps I would like to ask you what is your suggestion for fixing it.
Best Regards,
- Thu Jan 03, 2019 2:02 pm
- Forum: Vensim
- Topic: 'Vec elm map' error
- Replies: 8
- Views: 4303
Re: 'Vec elm map' error
Hi There are two difficulties in your formulation. The first is the correct use of the vector elm map and the possibility to use a simpler formula as explained in the link above or eventually the vector select explained by Tom. And once you are able to use a simpler formulation of the vector elm ma...
- Sun Dec 30, 2018 4:13 pm
- Forum: Vensim
- Topic: 'Vec elm map' error
- Replies: 8
- Views: 4303
Re: 'Vec elm map' error
Can you upload your model? I did not realise that "hour of day" is a subscript. It really helps us to help you if you can upload things so we can see exactly what you are doing. Unfortunately, I cannot upload the model. However, I have attached the graph and formula of respective part. As...
- Sun Dec 30, 2018 2:23 pm
- Forum: Vensim
- Topic: 'Vec elm map' error
- Replies: 8
- Views: 4303
Re: 'Vec elm map' error
Hi Avoid using the vector elm map function go to https://www.ventanasystems.co.uk/forum/viewtopic.php?f=2&t=3192&p=22055&hilit=vector+elm+map#p22055 It is good too setting the use stricte testing in the model<settings<units equiv window Regards. JJ Thanks for the help. Can you help me h...
- Sun Dec 30, 2018 1:02 pm
- Forum: Vensim
- Topic: 'Vec elm map' error
- Replies: 8
- Views: 4303
Re: 'Vec elm map' error
I'd start by simplifying things. First of all create a new parameter that is parameter 1 = hour of year/Hour unit+EndUse Region-1-1 and one that is parameter 2 = Hours per Year/Hour unit*year unit Now a 3rd parameter = MODULO(parameter 1,parameter 2) And see what the value of this is. My guess is t...
- Sat Dec 29, 2018 5:46 pm
- Forum: Vensim
- Topic: 'Vec elm map' error
- Replies: 8
- Views: 4303
'Vec elm map' error
Hi, I have one constant variable in the model as ‘Wind production as Fraction of Peak’ which it has two subscripts ( day of year ,hour of day). This variable is used in another variable called ‘wind onshore production this hour’ which its formula is as follows: Wind onshore production this hour[Endu...