units check errors
units check errors
Hello, I want to ask what this unit error means?The error screenshot is in the attachment
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Re: units check errors
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: units check errors
I suspect this is due to the use of DELAY1 with numerical parameters. For example, if you use DELAY1(input, 3, 0), the 3 and 0 don't have units. If instead you use DELAY1(input, delay time, 0) the time constant is properly dimensioned. This is also essential good practice, because it exposes the delay to sensitivity analysis or other testing.
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Re: units check errors
Hello, do you mean that my DELAY1 function is wrong? Is it because my unit does not define synonyms? Can you tell me how to solve this unit error in the figure?
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Re: units check errors
I'd suggest doing one of the many Vensim tutorials such as the one below. They will teach you how to define units.
http://www.public.asu.edu/~kirkwood/sysdyn/SDRes.htm
On this page you will find a really good Vensim PLE tutorial.
http://www.public.asu.edu/~kirkwood/sysdyn/SDRes.htm
On this page you will find a really good Vensim PLE tutorial.
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: units check errors
Thank you, I will take this tutorial.
Re: units check errors
I'm handicapped by not knowing the language, but it looks like you have two time units going - one given by the character in the denominator in the units expressions in the error message, and "day".
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Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
*/
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
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