Hi
As we know, stock variable is the integral of flow, if there is a stock with zero slope diagram, what could be the flow anyway?
I meant the Quality diagram in the attached file
best wishes
a stock with zero slope
a stock with zero slope
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Re: a stock with zero slope
Sorry, I do not understand what you are asking.
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Units are important!
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Re: a stock with zero slope
I meant as you can see in the picture, the behavior and structure of the actual quality is clear, suppose the formula of its inflow and outflow is not clear (for actual quality), can you suggest anything (inflow or outflow) that produce actual quality behavior?
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Re: a stock with zero slope
So you need some model structure that produces an immediate jump/fall in the stock?
Something like the following should get you started. This causes a jump at time = 10.
some stock = integ (inflow,0)
inflow = if then else ( time = 10, 20 , 0 )
Something like the following should get you started. This causes a jump at time = 10.
some stock = integ (inflow,0)
inflow = if then else ( time = 10, 20 , 0 )
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
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
http://www.bbc.co.uk/news/magazine-27509559
Re: a stock with zero slope
thx
it was a good start, By the way is there any way in vensim that can help us distinguish variable? for example name the constant one? how many constant are there? how many stock and etc.
best wishes
it was a good start, By the way is there any way in vensim that can help us distinguish variable? for example name the constant one? how many constant are there? how many stock and etc.
best wishes
Re: a stock with zero slope
If the stock of actual quality is essentially a step function, its net flow must be a discrete event, like a PULSE.
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Re: a stock with zero slope
thanks
I am really delighted to get acquainted with this site and its administers specially Tomfid who always helps me.
I am really delighted to get acquainted with this site and its administers specially Tomfid who always helps me.