rxMemoryEstimate: Estimate memory required by rxSolve() for a given dataset and...

In rxode2: Facilities for Simulating from ODE-Based Models

Estimate memory required by rxSolve() for a given dataset and model

Description

Accepts either a pre-summarized per-ID table (an rxMemSummary or any data.frame with nobs and ndoses columns) or a full event-table data.frame with an evid column. Model dimensions can be supplied via a compiled rxode2 model object or overridden individually.

Usage

rxMemoryEstimate(
  dat,
  model = NULL,
  control = NULL,
  neq = 1L,
  stateSize = neq,
  nlhs = 0L,
  npars = neq,
  neta = 0L,
  neps = 0L,
  ncov = 0L,
  nsim = 1L,
  cores = 1L,
  nMtime = 0L,
  extraCmt = 0L,
  linB = FALSE,
  nLlik = 0L,
  nIndSim = NULL,
  numLinSens = 0L,
  numLin = 0L
)

Arguments

dat	A rxMemSummary, a data.frame with nobs/ndoses columns, or a full event-table data.frame with an evid column. This can also be a serialized solve state file path, a solve state bundle list containing an events element, or an rxSolve object (using its stored solve events).
model	Optional rxode2 model object. When supplied, neq, nlhs, npars, extraCmt, linB, nMtime, nLlik, and nIndSim are extracted automatically.
control	Optional rxControl object. When supplied, cores, nsim, neta (from omega), neps (from sigma), and nLlik (adjusted by nLlikAlloc) are overridden automatically.
neq	Number of ODE states.
stateSize	Effective state.size() seen by the solver. Equals neq for pure ODE models; may differ for linCmt-only models. Defaults to neq.
nlhs	Number of LHS (calculated) output variables.
npars	Number of model parameters (drives gpars size).
neta	Number of random effects (etas).
neps	Number of residual-error levels (epsilons).
ncov	Number of time-varying covariates.
nsim	Number of simulations.
cores	Number of parallel OMP threads.
nMtime	Number of model measurement times.
extraCmt	Extra compartments (0, 1 = depot, 2 = depot+central).
linB	TRUE/1 if using a linear-compartment model.
nLlik	Number of log-likelihood terms (FOCEi use).
nIndSim	Per-individual simulation count. Defaults to neta + neps when not supplied explicitly.
numLinSens	Number of linear sensitivity parameters (FOCEi + linCmt).
numLin	Number of linear compartment terms (FOCEi + linCmt).

Details

The byte counts are computed by rxMemoryComponents_() which calls the same rxFillMemLayout() used by the real allocator, so any change to the allocation formulas propagates here automatically.

Value

A named list of class "rxMemoryEstimate" whose elements are raw byte counts plus outputData, ramBytes, freeRamBytes, total, sizeofInd, and rxLlikSaveSize.

Examples

mod <- rxode2::rxode2({
  d/dt(depot)  <- -ka * depot
  d/dt(center) <- ka * depot - cl / v * center
  cp           <- center / v
})

ev <- rxode2::et(amt = 100, ii = 24, until = 168) |>
  rxode2::et(seq(0, 168, by = 1))

# Basic estimate from event table and model
rxMemoryEstimate(as.data.frame(ev), model = mod)

# With rxControl: population simulation with omega and 4 cores
ctrl <- rxode2::rxControl(
  cores = 4L,
  omega = lotri::lotri(eta.ka ~ 0.09, eta.cl ~ 0.04)
)
rxMemoryEstimate(as.data.frame(ev), model = mod, control = ctrl)

rxode2 documentation built on July 28, 2026, 5:08 p.m.