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module NMap : Stats.Finbij.S with type elt = Free_variable.t

type measure = Measure of Maths.vector

type constrnt = Full of Costlang.affine * measure

type problem =
  | Non_degenerate of {
      lines : constrnt list;
      input : Maths.matrix;
      output : Maths.matrix;
      nmap : NMap.t;
    }
  | Degenerate of {predicted : Maths.matrix; measured : Maths.matrix}

type scores = {
  (* R2 score is uninformative when the input is constant. (e.g. constant model)
     We use `None` for the R2 score of such models. *)
  r2_score : float option;
  rmse_score : float;
  tvalues : (Free_variable.t * float) list;
}

val scores_encoding : scores Data_encoding.t

val pp_scores : Format.formatter -> scores -> unit

val scores_to_csv_column : string * Namespace.t -> scores -> Csv.csv

type solution = {
  mapping : (Free_variable.t * float) list;
  weights : Maths.matrix;
  intercept_lift : float;
      (** The diff required to overestimate all measurements by the predictions.
          This diff should be applied to the intercept parameter
          when this solution is for the allocation costs. *)
  scores : scores;
}

type solver =
  | Ridge of {alpha : float}
  | Lasso of {alpha : float; positive : bool}
  | NNLS

type error_statistics

val pp_error_statistics : Format.formatter -> error_statistics -> unit

(** Compute prediction error *)
val compute_error_statistics :
  predicted:Maths.matrix -> measured:Maths.matrix -> error_statistics

(** [make_problem ~data ~model ~overrides] makes a benchmark problem for a solver
    from the workload [data] and the model [model]. [overrides] specify the variables
    whose values are already known.
*)
val make_problem :
  data:'workload Measure.workload_data ->
  model:'workload Model.t ->
  overrides:(Free_variable.t -> float option) ->
  problem

(** [solve_problem problem solver] solves [problem] using [solver]. *)
val solve_problem : problem -> solver -> solution

val problem_to_csv : problem -> Csv.csv

val mapping_to_csv : (Free_variable.t * float) trace -> Csv.csv

val solution_to_csv : solution -> Csv.csv option