{
  "name": "Grouped Barplot Implementation Matrix Across R Graphics Frameworks",
  "description": "Original comparative matrix compiled from the R Core Team graphics documentation, ggplot2 reference manuals, and lattice specification, detailing data structure inputs, dodging parameters, error bar alignment, and coordinate handling for grouped categorical charts in R.",
  "page": "https://casrai.org/guides/barplot-by-group-in-r",
  "publisher": "CASRAI",
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "dateModified": "2026-11-14T15:31:49Z",
  "temporalCoverage": null,
  "spatialCoverage": null,
  "columns": [
    {
      "name": "Framework and Function",
      "unit": "",
      "description": "Graphics engine and primary function name"
    },
    {
      "name": "Primary Input Data Structure",
      "unit": "",
      "description": "Required data shape for grouped rendering"
    },
    {
      "name": "Grouping Parameter",
      "unit": "",
      "description": "Argument that enables side-by-side grouped placement"
    },
    {
      "name": "Group Spacing Mechanism",
      "unit": "",
      "description": "Default spacing behavior between adjacent grouped bars"
    },
    {
      "name": "Missing Level Handling",
      "unit": "",
      "description": "Mechanism to prevent bar widening on empty factor levels"
    },
    {
      "name": "Error Bar Integration Method",
      "unit": "",
      "description": "Function and syntax used to overlay interval bars"
    },
    {
      "name": "Coordinate Return",
      "unit": "",
      "description": "Availability of returned geometric coordinates"
    }
  ],
  "rows": [
    {
      "Framework and Function": "Base R graphics::barplot",
      "Primary Input Data Structure": "Numeric matrix or 2D table",
      "Grouping Parameter": "beside = TRUE",
      "Group Spacing Mechanism": "c(0, 1) default inner/outer ratio",
      "Missing Level Handling": "Requires explicit zero count in matrix",
      "Error Bar Integration Method": "arrows() using returned midpoint coordinates",
      "Coordinate Return": "Invisibly returns matrix of bar center x-coordinates"
    },
    {
      "Framework and Function": "ggplot2::geom_col",
      "Primary Input Data Structure": "Tidy data frame in long format",
      "Grouping Parameter": "position = position_dodge()",
      "Group Spacing Mechanism": "width parameter inside position_dodge()",
      "Missing Level Handling": "preserve = 'single' prevents lone bar widening",
      "Error Bar Integration Method": "geom_errorbar() with matched position_dodge(0.9)",
      "Coordinate Return": "Extracted via ggplot_build() internal data"
    },
    {
      "Framework and Function": "ggplot2::geom_bar",
      "Primary Input Data Structure": "Unaggregated tidy data frame (factors)",
      "Grouping Parameter": "position = position_dodge()",
      "Group Spacing Mechanism": "stat_count() with dodge position adjustment",
      "Missing Level Handling": "preserve = 'single' maintains constant bar width",
      "Error Bar Integration Method": "Requires pre-summarized data via geom_col instead",
      "Coordinate Return": "Extracted via ggplot_build() internal data"
    },
    {
      "Framework and Function": "lattice::barchart",
      "Primary Input Data Structure": "Formula interface with table or data frame",
      "Grouping Parameter": "groups aesthetic with auto.key",
      "Group Spacing Mechanism": "Trellis panel side-by-side positioning",
      "Missing Level Handling": "Factor level preservation via drop.unused.levels",
      "Error Bar Integration Method": "Custom panel function with panel.arrows()",
      "Coordinate Return": "Accessed via trellis.panelArgs() function"
    }
  ],
  "sources": [
    {
      "title": "R Core Team: graphics::barplot Manual",
      "url": "https://stat.ethz.ch/R-manual/R-devel/library/graphics/html/barplot.html",
      "accessed": "2026-11-14"
    },
    {
      "title": "Wickham et al.: ggplot2 geom_bar and geom_col Reference",
      "url": "https://ggplot2.tidyverse.org/reference/geom_bar.html",
      "accessed": "2026-11-14"
    },
    {
      "title": "Wickham et al.: ggplot2 position_dodge Reference",
      "url": "https://ggplot2.tidyverse.org/reference/position_dodge.html",
      "accessed": "2026-11-14"
    },
    {
      "title": "Sarkar, D.: lattice barchart Reference",
      "url": "https://stat.ethz.ch/R-manual/R-devel/library/lattice/html/barchart.html",
      "accessed": "2026-11-14"
    }
  ]
}