problem whit model

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viyana
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problem whit model

Postby viyana » Tue Feb 02, 2016 9:05 pm

Dear all
I can not understand error in my project
Can anyone check my model and help me
Attachments
project1.mdl
(7.91 KiB) Downloaded 44 times

Administrator
Super Administrator
Posts: 2848
Joined: Wed Mar 05, 2003 3:10 am

Re: problem whit model

Postby Administrator » Wed Feb 03, 2016 8:02 am

"THE UNEMPLOYMENT RATE" is a lookup table, you are using it like a standard variable. I would try and fix it, but the model has no units so I've got no idea what the x axis is for the lookup.

You need to review
http://vensim.com/documentation/index.html?usr08.htm
and there is a video at
http://vensim.com/lookups-in-vensim/
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/viewtopic.php?f=2&t=4391

Units are important!
http://www.bbc.co.uk/news/magazine-27509559

sem
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Posts: 3
Joined: Thu Jun 09, 2016 8:22 am
Vensim version: PLE

Re: problem whit model

Postby sem » Thu Jun 09, 2016 8:29 am

Hello, i have also some difficulties with a model.

I am using a lookup function (variable standard natural fractional growth buffalo) in this model (see attachment), however i keep getting the following warning: lookup out of bounds at 2000 Above -Standard fractional natural growth rate buffalo- computing -natural growth rate Buffalo-.

I tried numerous things, however I can't get the lookup function working. Can i get some specific help on how to make my model work and able to simulate?!

Regards,

Sem
Attachments
deer & buffalo.mdl
(8.1 KiB) Downloaded 30 times

Administrator
Super Administrator
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Joined: Wed Mar 05, 2003 3:10 am

Re: problem whit model

Postby Administrator » Thu Jun 09, 2016 8:34 am

There are many threads already on the forum which discuss the same warning message.

See
viewtopic.php?f=2&t=5477&p=19142&hilit=lookup+out+of+bounds#p19142
and
viewtopic.php?f=2&t=4521&p=15267&hilit=lookup+out+of+bounds#p15267
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/viewtopic.php?f=2&t=4391

Units are important!
http://www.bbc.co.uk/news/magazine-27509559

sem
Junior Member
Posts: 3
Joined: Thu Jun 09, 2016 8:22 am
Vensim version: PLE

Re: problem whit model

Postby sem » Thu Jun 09, 2016 8:39 am

I did already see those post, but my lookup table just doesn't get recognized as a lookup, ofcourse i did try the tips from the post, but they do not work!

Administrator
Super Administrator
Posts: 2848
Joined: Wed Mar 05, 2003 3:10 am

Re: problem whit model

Postby Administrator » Thu Jun 09, 2016 8:44 am

Can you check your original question please. There is no variable called "variable standard natural fractional growth buffalo" or "standard natural fractional growth buffalo".

What do you mean by "doesn't get recognized as a lookup"? If you are getting that warning, then it must be recognized as a lookup, only lookups generate the warning.
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/viewtopic.php?f=2&t=4391

Units are important!
http://www.bbc.co.uk/news/magazine-27509559

sem
Junior Member
Posts: 3
Joined: Thu Jun 09, 2016 8:22 am
Vensim version: PLE

Re: problem whit model

Postby sem » Thu Jun 09, 2016 8:47 am

The name of the variable is: standard fractional natural growth rate buffalo.

What i was meaning to say, is that eventhough my x-y axes of the lookup are correct (i think), and after trying a lot of things, i am still getting this warning.

Administrator
Super Administrator
Posts: 2848
Joined: Wed Mar 05, 2003 3:10 am

Re: problem whit model

Postby Administrator » Thu Jun 09, 2016 9:03 am

It's bad practice to embed equations within other equations.

Create a new temporary variable and make the equation "Buffalo Population*effect of food consumption on natural growth rate buffalo". This is what you are passing to the lookup (which is way outside the bounds).
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/viewtopic.php?f=2&t=4391

Units are important!
http://www.bbc.co.uk/news/magazine-27509559


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