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Calculate additional grain-size indices

Source: R/engineering.R
gs_grain_size_indices.Rd

gs_grain_size_indices() calculates additional grain-size indices from boundary-based D-value interpolation and a fine-content threshold. Returned indices include coefficient of uniformity (Cu), coefficient of curvature (Cc), Trask sorting, Trask skewness, fine content, and fine equivalent.

Usage

gs_grain_size_indices(
  x,
  fine_threshold_um = 62.5,
  interpolation_scale = "phi",
  extrapolate = "error"
)

Arguments

x

A valid gsd_tbl object.

fine_threshold_um

Fine-content threshold in micrometers.

interpolation_scale

Interpolation scale passed to gs_d_values() and gs_percent_finer().

extrapolate

Extrapolation behavior passed to gs_d_values() and gs_percent_finer().

Value

A tibble with one row per sample and grain-size indices.

Details

D10/D25/D30/D50/D60/D75 are computed by gs_d_values(), including its deterministic tie-breaking rule for percentiles that fall on a plateau caused by consecutive zero-retained classes (see gs_d_values() for details); fine_content_percent is computed by gs_percent_finer(), which is not affected by that tie-breaking rule (see its documentation).