R/209_reductions_dgp2dcp_canonicalizers_geo_mean_canon.R

In CVXR: Disciplined Convex Optimization

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## DO NOT EDIT THIS FILE!! EDIT THE SOURCE INSTEAD: rsrc_tree/reductions/dgp2dcp/canonicalizers/geo_mean_canon.R
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## CVXPY SOURCE: reductions/dgp2dcp/canonicalizers/geo_mean_canon.py
## DGP canonicalizer for GeoMean: geo_mean(x, p) -> (1/sum(p)) * sum(p_i * x_i)
## In log-space, geometric mean is affine (weighted average of logs).

.dgp_geo_mean_canon <- function(expr, args) {
  p_vec <- expr@p
  x <- args[[1L]]
  n <- length(p_vec)
  out <- p_vec[1L] * x[1]
  if (n > 1L) {
    for (i in 2L:n) {
      out <- out + p_vec[i] * x[i]
    }
  }
  result <- (1.0 / sum(p_vec)) * out
  list(result, list())
}