make parameters() show fixed effects restricted to 0

Fixes #715

R/utils.R

@@ -99,3 +99,37 @@
 .is_semLme <- function(x) {
   all(inherits(x, c("sem", "lme")))
 }
+
+
+.insert_row_at <- function(data, row, index, default_value = NA) {
+  # add missing columns
+  new_columns <- setdiff(colnames(data), colnames(row))
+  if (length(new_columns) > 0) {
+    row[new_columns] <- default_value
+  }
+  # match column order
+  row <- row[match(colnames(data), colnames(row))]
+
+  # insert row
+  if (index == 1) {
+    rbind(row, data)
+  } else if (index == nrow(data)) {
+    rbind(data, row)
+  } else {
+    rbind(data[1:(index - 1), ], row, data[index:nrow(data), ])
+  }
+}
+
+
+.find_factor_levels <- function(data) {
+  out <- lapply(colnames(data), function(i) {
+    v <- data[[i]]
+    if (is.factor(v)) {
+      paste0(i, levels(v))
+    } else {
+      NULL
+    }
+  })
+  names(out) <- names(data)
+  insight::compact_list(out)
+}

R/utils_format.R

@@ -280,6 +280,7 @@
                                              format = NULL,
                                              coef_name = NULL,
                                              zap_small = FALSE,
+                                             add_reference = FALSE,
                                              ...) {
   # default brackets are parenthesis for HTML / MD
   if ((is.null(ci_brackets) || isTRUE(ci_brackets)) && (identical(format, "html") || identical(format, "markdown"))) {
@@ -308,6 +309,11 @@
     x$Level <- NULL
   }
 
+  # add the coefficient for the base-(reference)-level of factors?
+  if (add_reference) {
+    x <- .add_reference_level(x)
+  }
+
   insight::format_table(
     x,
     pretty_names = pretty_names,
@@ -322,6 +328,29 @@
 }
 
 
+.add_reference_level <- function(params) {
+  # check if we have a model object, else return parameter table
+  model <- .get_object(params)
+  if (is.null(model)) {
+    params
+  }
+
+  # check if we have model data, else return parameter table
+  model_data <- insight::get_data(model)
+  if (is.null(model_data)) {
+    params
+  }
+
+  # find factors and factor levels and check if we have any factors in the data
+  factors <- .find_factor_levels(model_data)
+  if (!length(factors)) {
+    params
+  }
+
+  params
+}
+
+
 # The coefficient column in the printed output is renamed, based on the model.
 # But for instance, for random effects, however, which are on a different scale,
 # we want a different name for this column. Since print.parameters_model() splits