INTEG:Unable to understand the right hand side of this equation

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ciwei
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Posts: 4
Joined: Wed Jun 21, 2017 7:34 am
Vensim version: PLE

INTEG:Unable to understand the right hand side of this equation

Post by ciwei »

I used the Vensim demo app, and when I tried to build the rabbit population model, I ran into a problem, as shown below. Can you help me out? Thank you very much.

the level type,used Equations INTEG has errors shown below:
Errors:Unable to understand the right hand side of this equation.

Vensim version: Vensim PLE for Windows Version7.0 Limited Time Evaluation
Attachments
rabbit_test.mdl
(2.06 KiB) Downloaded 339 times
Administrator
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Re: INTEG:Unable to understand the right hand side of this equation

Post by Administrator »

Draw arrows from "births" to "population" and from "deaths" to "population", it should now be ok.
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ciwei
Junior Member
Posts: 4
Joined: Wed Jun 21, 2017 7:34 am
Vensim version: PLE

Re: INTEG:Unable to understand the right hand side of this equation

Post by ciwei »

Thank you very much.According to your method, the problem of horizontal variables population is solved, but the new problem is that the variable "births" is bad ,it's need population in the formula.

I refer to this site for example :https://www.vensim.com/documentation/Mo ... sample.htm
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Re: INTEG:Unable to understand the right hand side of this equation

Post by Administrator »

rabbit_test.mdl
(2.13 KiB) Downloaded 336 times
I'm not sure what the problem is, the model I've attached runs fine for me.
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391

Units are important!
http://www.bbc.co.uk/news/magazine-27509559
ciwei
Junior Member
Posts: 4
Joined: Wed Jun 21, 2017 7:34 am
Vensim version: PLE

Re: INTEG:Unable to understand the right hand side of this equation

Post by ciwei »

That's OK, thank you very much.I just got it wrong,thank you.
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