indexing within constraints - I am looking for help :)

[chris13337]

Hi,

I am using the OMPR package for a few months now and I, first of all, would like to thank you for the great effort you put into this!
I am having a problem while formulating a problem. This is a working code example from me:

` add_constraint(sum_expr(x[i]* help_matrix[i,1],i = 1:length(projection$proj_total)) <= 3) %>%

add_constraint(sum_expr(x[i]* help_matrix[i,2],i = 1:length(projection$proj_total)) <= 3) %>%

add_constraint(sum_expr(x[i]* help_matrix[i,3],i = 1:length(projection$proj_total)) <= 3) %>%

add_constraint(sum_expr(x[i]* help_matrix[i,4],i = 1:length(projection$proj_total)) <= 3) %>%

add_constraint(sum_expr(x[i]* help_matrix[i,5],i = 1:length(projection$proj_total)) <= 3) %>% `

is there a more efficient way to do it? ( I am sure there is one, but I am not able to implement it. I tried this:
add_constraint(sum_expr(x[i]* help_matrix[i,j],i = 1:length(projection$proj_total)) <= 3,j <- 1:5) %>%

but I get an error for this:
Fehler in check_for_unknown_vars_impl(model, the_ast) :
The expression contains a variable that is not part of the model.

how can this be solved?
I am looking forward to your answer!

Kind regards,

Christian Schumacher

[dirkschumacher]

👋 Please provide a reproducible example (https://reprex.tidyverse.org/) if possible, then it is easier to find the problem.
A good debugging strategy is make the model as small as possible and then to add constraints one by one to see which one breaks.