taxa (version 0.1.0)

sample_frac_obs: Sample a proportion of observations from taxmap()

Description

Randomly sample some proportion of observations from a taxmap() object. Weights can be specified for observations or their taxa. See dplyr::sample_frac() for the inspiration for this function.

obj$sample_frac_obs(target, size, replace = FALSE,
  taxon_weight = NULL, obs_weight = NULL,
  use_supertaxa = TRUE, collapse_func = mean, ...)
sample_frac_obs(obj, target, size, replace = FALSE,
  taxon_weight = NULL, obs_weight = NULL,
  use_supertaxa = TRUE, collapse_func = mean, ...)

Arguments

obj

(taxmap()) The object to sample from.

target

The name of the table in obj$data to filter

size

(numeric of length 1) The proportion of observations to sample.

replace

(logical of length 1) If TRUE, sample with replacement.

taxon_weight

(numeric) Non-negative sampling weights of each taxon. If use_supertaxa is TRUE, the weights for each taxon in an observation's classification are supplied to collapse_func to get the observation weight. If obs_weight is also specified, the two weights are multiplied (after taxon_weight for each observation is calculated).

obs_weight

(numeric) Sampling weights of each observation. If taxon_weight is also specified, the two weights are multiplied (after taxon_weight for each observation is calculated).

use_supertaxa

(logical or numeric of length 1) Affects how the taxon_weight is used. If TRUE, the weights for each taxon in an observation's classification are multiplied to get the observation weight. If FALSE just the taxonomic level the observation is assign to it considered. Positive numbers indicate the number of ranks above the each taxon to use. 0 is equivalent to FALSE. Negative numbers are equivalent to TRUE.

collapse_func

(function of length 1) If taxon_weight option is used and supertaxa is TRUE, the weights for each taxon in an observation's classification are supplied to collapse_func to get the observation weight. This function should take numeric vector and return a single number.

...

Additional options are passed to filter_obs().

Value

An object of type taxmap()

See Also

Other taxmap manipulation functions: arrange_obs, arrange_taxa, filter_obs, filter_taxa, mutate_obs, sample_frac_taxa, sample_n_obs, sample_n_taxa, select_obs, transmute_obs

Examples

# NOT RUN {
sample_frac_obs(ex_taxmap, "info", 0.5)

# }