How to call variable value of previous time period in a equation

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amitkaram
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Joined: Sun Nov 19, 2017 2:46 am
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How to call variable value of previous time period in a equation

Post by amitkaram »

I want to use the variable value of previous time periods , that is of (t-1) or (t-2) in the equation for time t.How do i do that
I will be very grateful if i could get help on this
amitkaram
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Posts: 10
Joined: Sun Nov 19, 2017 2:46 am
Vensim version: PLE

Re: How to call variable value of previous time period in a equation

Post by amitkaram »

I understand about delay fixed function, but it treats variable on left side as level variable.In my case, variable on left side is a auxiliary variable whose value is changing every time period.
amitkaram
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Posts: 10
Joined: Sun Nov 19, 2017 2:46 am
Vensim version: PLE

Re: How to call variable value of previous time period in a equation

Post by amitkaram »

Also, I am unable to use GET TIME VALUE function to know the current value of time. Vensim says that this function is not operable with this configuration.What option do I have other than above function to get the current time value.
tomfid
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Re: How to call variable value of previous time period in a equation

Post by tomfid »

Just use the time variable.
tomfid
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Re: How to call variable value of previous time period in a equation

Post by tomfid »

You just need to delay whatever it is on the right hand side of the equation that you need. But be careful.
http://metasd.com/2017/11/discrete-time-stinks/
amitkaram
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Joined: Sun Nov 19, 2017 2:46 am
Vensim version: PLE

Re: How to call variable value of previous time period in a equation

Post by amitkaram »

Thanks @tomfid :)
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