Units do not match
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Units do not match
Right hand and left hand unit of replicator dynamics equation do not match
replicator dynamic equation:dy/dt=y(1-y)(URC-URN)
The left hand:percent/Month
The right hand:CNY
Although Units equivalents [percent/Month,CNY] were set, this problem still exist.
Thank you for your answer
replicator dynamic equation:dy/dt=y(1-y)(URC-URN)
The left hand:percent/Month
The right hand:CNY
Although Units equivalents [percent/Month,CNY] were set, this problem still exist.
Thank you for your answer
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Re: Units do not match
Can you upload the model?
And what units are "CNY"? I've never heard of this as a unit/dimension.
And what units are "CNY"? I've never heard of this as a unit/dimension.
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
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Re: Units do not match
Thank you for your reply.
I have been uploaded the model.
The unit "CNY" is the chinese currency unit.
I have been uploaded the model.
The unit "CNY" is the chinese currency unit.
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- SD model of tripartite evolutionary game under F-scheme.mdl
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Re: Units do not match
First of all, remove the units equivalence "percent/Month,CNY". CNY is currency, percent/month is definitely not. You use units equiveillances for things like "month,months" or "person,persons,people,human".
Looking at your model, start by putting in units for all of the parameters. These units should match reality, if something is an interest rate, it should be something like percent/year or percent/month etc.
I've got no idea what all the parameters refer to in this model so cannot really offer any more advice.
Looking at your model, start by putting in units for all of the parameters. These units should match reality, if something is an interest rate, it should be something like percent/year or percent/month etc.
I've got no idea what all the parameters refer to in this model so cannot really offer any more advice.
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
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- Junior Member
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Re: Units do not match
Thank you for your help.
I want to set the rate(variable)'s unit in eqution: dx/dt=x'(t)=a×x(t),a is const.
But, units do not match(left and right hand).
x(t) represent the probability of selecting one strategy, i set the unit: Dmnl,
but the unit of [dx/dt] must be the 1/Month(or other time type), so i can not match the units between the 2 sides.
Could I explain my question clearly?
Wish for your help.
Thx...
I want to set the rate(variable)'s unit in eqution: dx/dt=x'(t)=a×x(t),a is const.
But, units do not match(left and right hand).
x(t) represent the probability of selecting one strategy, i set the unit: Dmnl,
but the unit of [dx/dt] must be the 1/Month(or other time type), so i can not match the units between the 2 sides.
Could I explain my question clearly?
Wish for your help.
Thx...
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Re: Units do not match
Units should always be very straightforward. Always enter what the parameter would be measured in in the real world.
Can you upload the model? It's difficult to offer advice with so little to work on.
I'd suggest that the probability is correct, that should be dimensionless. Cannot really offer any more advice without seeing the model.
Can you upload the model? It's difficult to offer advice with so little to work on.
I'd suggest that the probability is correct, that should be dimensionless. Cannot really offer any more advice without seeing the model.
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
-
- Junior Member
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- Vensim version: PLE
Re: Units do not match
I have been uploading my model.
I am waiting for your help.
Thx
I am waiting for your help.
Thx
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- simplify sys1.mdl
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Re: Units do not match
The unitrate was set as Tolerances for Arithmetic Sequences, i.e. dx/dt=Δx, the unit of left is 1/time, but the unit of right is 1.Administrator wrote: ↑Tue Apr 18, 2023 10:32 am Units should always be very straightforward. Always enter what the parameter would be measured in in the real world.
Can you upload the model? It's difficult to offer advice with so little to work on.
I'd suggest that the probability is correct, that should be dimensionless. Cannot really offer any more advice without seeing the model.
How can I match the units?
Thx
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Re: Units do not match
Fist thing, δx should have units of DMNL/month as it's a rate of change.
I cannot really offer any more assistance as the model is not documented, I've got no idea what things like "L1" are (or if the units for it are even correct).
I cannot really offer any more assistance as the model is not documented, I've got no idea what things like "L1" are (or if the units for it are even correct).
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
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Re: Units do not match
When I simulate, there will be a variable out of range fault.Administrator wrote: ↑Thu Apr 20, 2023 1:41 pm Fist thing, δx should have units of DMNL/month as it's a rate of change.
I cannot really offer any more assistance as the model is not documented, I've got no idea what things like "L1" are (or if the units for it are even correct).
How can I debug?
I am waiting for your help.
Thx
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- variable D-1.jpg (136.27 KiB) Viewed 5789 times
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- fomula.docx
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- simplify sys1.mdl
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Re: Units do not match
This is the next variable definition.lagraberry wrote: ↑Mon Apr 24, 2023 6:39 amWhen I simulate, there will be a variable out of range fault.Administrator wrote: ↑Thu Apr 20, 2023 1:41 pm Fist thing, δx should have units of DMNL/month as it's a rate of change.
I cannot really offer any more assistance as the model is not documented, I've got no idea what things like "L1" are (or if the units for it are even correct).
How can I debug?
I am waiting for your help.
Thx
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- variable D-2.jpg (103.73 KiB) Viewed 5788 times
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Re: Units do not match
By multiplying the right-hand side of the equation by this conversion factor, you can ensure that the units match. The modified equation would then be:
dy/dt = y(1-y) * conversion_factor * (URC - URN)
dy/dt = y(1-y) * conversion_factor * (URC - URN)