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Dependent parameters - What are they?

Posted: 24 Aug 2016 22:57
by Christo P
As a beginner of openLCA usage I often read the user guides available and try to understand and test the application features.
Now I am creating a process of my experimental model (the model comprises several processes) and unexpectedly for me, I encountered a problem – I'm not sure I can define process parameters. According to the instructions given on "http://www.openlca.org/documentation/in ... s_settings" these should be "local" (for the same process) parameters, but in openLCA v. 1.4.2 there is not an option to defining local parameters. The command sequence for such task in v. 1.4.2 is different (from descriptions given in above source) and the editor accepts only global and "dependent" parameters. Surching in the help resources I could not find a definition for "dependent" parameter. Maybe the term "dependent" is a substitution of "local" but maybe that's not true.
So I wonder where the "local paremeters" have gone and do they exist in openLCA 1.4.2 (+ v.1.5) at all?. And, please, explain the function and usage of the "dependent" parameter.

Thanks in advance.
Chris

Re: Dependent parameters - What are they?

Posted: 26 Aug 2016 01:00
by aciroth
Hi Chris,
it is not that complicated: A dependent parameter depends on other parameters.
E.g.:
a = 2 (a is independent parameter);
b = a+1 (b is dependent parameter).
The link you mention refers to version 1.3 where this was indeed different.
Hth,
Andreas

Re: Dependent parameters - What are they?

Posted: 26 Aug 2016 17:59
by Christo P
Thank you Andreas,
From your reply I understand that in openLCA 1.4.x and higher versions exist only global parameters. If that is true, it means that every parameter (defined in the latest versions) is a global parameter and must have an unique name.
Best regards.
Chris

Re: Dependent parameters - What are they?

Posted: 28 Aug 2016 13:49
by aciroth
Hi Chris,
no, in version 1.4 and higher there are also parameters for processes, product systems, LCIA methods, and global parameters. These have formerly been called local parameters (in contrast to global parameters). Dependent parameters can be used just as independent parameters. And I tried to provide a definition in the post below (dependent parameters are those that depend on other parameters).
Hth,
Andreas

Re: Dependent parameters - What are they?

Posted: 30 Aug 2016 23:24
by Christo P
Hi Andreas,thank you for your second reply of the topic.
I understood the meaning of “dependent” parameter and its usage.
But, please, let me ask you one more question because you wrote:
“in version 1.4 and higher there are also parameters for processes, product systems, LCIA methods, and global parameters. These have formerly been called local parameters (in contrast to global parameters)”...
When I am in a process (of my model in openLCA) and after clicking the Parameters Tab, the window that opens gives the options for entering two groups of parameters: input and dependent parameters, both of them under Global parameters header. So, if I define for those process parameters (input and dependent), are my parameters at the same time Global? (for the database, or for an entire multi-process product system).