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dirkschumacher / ompr

R package to model Mixed Integer Linear Programs
https://dirkschumacher.github.io/ompr/
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Error Code "Error: object 'x' not found" #410

Open donojazz opened 2 years ago

donojazz commented 2 years ago

Modelling techniques in OMPR using MILPModel date: "2018-08-11". Just downloaded rmarkdown::github_document and tried to run. Got two instances of "Error: object 'x' not found" at R chunks 230-234, 237-239, I'm new to MILP Modeling and not sure if this is an issue. The generated Markdown seems to run, but the error codes show up in the R script. Thanks for the help. I really like your product. I am interested in Warehousing problems and that code ran perfectly. Thank again... Jim

sbmack commented 2 years ago

I am interested in Warehousing problems and that code ran perfectly. Thank again... Jim

Jim, any posted MIPModel formulations of real cases can be very helpful. If you could also post an anonymized version of your Warehousing model that would be great. I am especially interested in formulating compound indexes. Thanks. SteveM

donojazz commented 2 years ago

Here is an example, without code, of a recent presentation at an R in Supply Chain meetup that got me very interested in a similar solution. That briefing led me to find Dirk and his OMPR site. Good slides of data used and supporting R packages. https://www.youtube.com/watch?v=vRbUM0n_nb8

dirkschumacher commented 2 years ago

Can you create minimal, reproducible example showing the problem here? Ideally using the {reprex} package.

datadrivensupplychain commented 2 years ago

Hi @donojazz , this is Ralph. If you want to get started with warehouse network design using ompr, I wrote a TDS article on it a while ago. https://towardsdatascience.com/supply-chain-design-using-r-unconstrained-warehouse-customer-alignment-9ec11c1e4345

Hope this helps Ralph