Specific Variables for Each Time Step

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aalto-comnet
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Vensim version: DSS

Specific Variables for Each Time Step

Post by aalto-comnet »

Hello!

Newbie question perhaps: How can I set specific values in a variable for each time step?

So let's say 10 specific values, for an initial time of 1, final time of 10, and time step of 1.

Thank you in advance!
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Re: Specific Variables for Each Time Step

Post by Administrator »

You could use a lookup table.

What are these values? Where do they come from?
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aalto-comnet
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Re: Specific Variables for Each Time Step

Post by aalto-comnet »

Thanks for the reply!

They are not saved in a file. I would just like to add them manually.
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Re: Specific Variables for Each Time Step

Post by Administrator »

A lookup could be used.
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aalto-comnet
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Re: Specific Variables for Each Time Step

Post by aalto-comnet »

I am trying a lookup, but then I receive an error for the variables that it points to: "... is a special type and cannot be used as a normal variable".

So what I need is to output one value from the lookup for each time iteration as far as I understand.
aalto-comnet
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Posts: 37
Joined: Fri Dec 07, 2018 9:20 am
Vensim version: DSS

Re: Specific Variables for Each Time Step

Post by aalto-comnet »

To be more specific,

in the NETWORKE.mdl model of Chapter 10 that can be found in the VENSIMMO.zip here:

http://www.mhhe.com/business/opsci/sterman/models.mhtml

the Total Demand variable is a constant number.

I would like to give specific values for each time step as described. I change the Type of the variable to Lookup, as suggested, and give the values that I want, but then I receive the error that I mention above.
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