change integration unit

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MartinNT
Junior Member
Posts: 8
Joined: Sat Oct 15, 2005 4:31 pm

change integration unit

Post by MartinNT »

How do I solve this error?
It seems like Vensim automatically integrates with months instead of years.

Error in units for the following equation:
Rabbit Population =
INTEG( birth rate
- death rate ,
1000)
Rabbit Population --> rabbit
birth rate --> rabbit/Year
death rate --> rabbit/Year

Analysis of units error:
Right hand and left hand units do not match
Rabbit Population
Has units: rabbit
INTEG( birth rate
- death rate ,
1000)
Has units: Month*rabbit/Year
LAUJJL
Senior Member
Posts: 1477
Joined: Fri May 23, 2003 10:09 am
Vensim version: DSS

integration error

Post by LAUJJL »

Hi

Vensim integrates using the time step specified in the settings, which in your case must be one month.
And you use as rate rabbit/ year, and should use rabbit / month.
Regards.
J.J. Laublé
MartinNT
Junior Member
Posts: 8
Joined: Sat Oct 15, 2005 4:31 pm

Post by MartinNT »

Thank you - I'm still learning the program...:)
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