Hi,
I have searched what I need to know in this forum but no luck.
My question are:
1. How do I create variable with "data type" ?
2. Is that possible to use "accumulate function" to accumulate "a stock variable" ?
3. Is that "get data at time function" only works for "data type" ?
data type
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Re: data type
In the equation editor, there is a field titled "Type", select "Data" from here.
To accumulate something, you use a stock.
Correct. What do you need to do?
The following might help.
http://www.vensim.com/documentation/ind ... ?usr16.htm
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Re: data type
1. http://vensim.com/documentation/usr16.htm
2. You can use CUMULATE/CUMULATEF to calculate cumulative values of data, but it's not the same as a regular stock (INTEG). http://vensim.com/documentation/fn_cumulate.htm
3. Correct. http://vensim.com/documentation/fn_get_data_at_time.htm
2. You can use CUMULATE/CUMULATEF to calculate cumulative values of data, but it's not the same as a regular stock (INTEG). http://vensim.com/documentation/fn_cumulate.htm
3. Correct. http://vensim.com/documentation/fn_get_data_at_time.htm
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Re: data type
Hi again,
What I meant is when I choose "constant" or "auxiliary" or "level",
I can type any value(s) or expressions.
But, for "data type", I did not any spaces to type values or mathematical expressions.
Could you please tell me how to create a variable with a "data type" ?
Next, I have a stock (A) and model's time is month.
I want to get a cumulative value of A for every year.
What shall I do ?
What I meant is when I choose "constant" or "auxiliary" or "level",
I can type any value(s) or expressions.
But, for "data type", I did not any spaces to type values or mathematical expressions.
Could you please tell me how to create a variable with a "data type" ?
Next, I have a stock (A) and model's time is month.
I want to get a cumulative value of A for every year.
What shall I do ?
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- Super Administrator
- Posts: 4590
- Joined: Wed Mar 05, 2003 3:10 am
Re: data type
I'd start by doing a Vensim tutorial. On this page you will find a really good Vensim PLE tutorial.
http://www.public.asu.edu/~kirkwood/sysdyn/SDRes.htm
This will teach you what you need to get started.
http://www.public.asu.edu/~kirkwood/sysdyn/SDRes.htm
This will teach you what you need to get started.
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Re: data type
The user guide link above explains the data options, but the short answer is, set the Sub-Type of the data variable to "Equation" in the equation editor.
A stock is an accumulation, so I'm not quite sre what you're asking.
A stock is an accumulation, so I'm not quite sre what you're asking.
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