catching calls to unsupported aggregation function in R

R/acro_tables.R

@@ -20,12 +20,42 @@ acro_crosstab <- function(index, columns, values = NULL, rownames = NULL, colnam
     stop("ACRO has not been initialised. Please first call acro_init()")
   }
 
-  py_table <- acroEnv$ac$crosstab(index, columns, values = values, rownames = rownames, colnames = colnames, aggfunc = aggfunc, margins = margins, margins_name = margins_name, dropna = dropna, normalize = normalize, show_suppressed = show_suppressed)
+  # Convert the values into a NumPy array so that the Python ACRO crosstab function accepts them
+  np <- reticulate::import("numpy", convert = TRUE)
+  py_values <- if (!is.null(values)) np$array(values) else NULL
+
+  py_table <- tryCatch(
+    {
+      acroEnv$ac$crosstab(index, columns, values = py_values, rownames = rownames, colnames = colnames, aggfunc = aggfunc, margins = margins, margins_name = margins_name, dropna = dropna, normalize = normalize, show_suppressed = show_suppressed)
+    },
+    error = function(e) {
+      # Check if Python threw the ValueError about an unsupported aggfunc
+      if (grepl("ValueError: aggfunc", e$message)) {
+        stop(
+          sprintf("Unsupported aggregation function provided: '%s'. Allowed functions are: mean, median, sum, std, count, mode.", aggfunc),
+          call. = FALSE
+        )
+      }
+      # 2. Check if Python threw the missing values column error
+      else if (grepl("If you pass an aggregation function to crosstab", e$message)) {
+        stop(
+          "If you pass an aggregation function to crosstab, you must also specify a single values column to aggregate over.",
+          call. = FALSE
+        )
+      }
+      # any other unexpected errors
+      else {
+        stop(e) # nocov
+      }
+    }
+  )
+
   table <- reticulate::py_to_r(py_table)
 
   return(table)
 }
 
+
 #' Compute a simple cross tabulation of two (or more) factors.
 #'
 #' @param index Values to group by in the rows.
@@ -152,7 +182,23 @@ acro_pivot_table <- function(data, values = NULL, index = NULL, columns = NULL,
   if (is.null(acroEnv$ac)) {
     stop("ACRO has not been initialised. Please first call acro_init()")
   }
-  py_table <- acroEnv$ac$pivot_table(data, values = values, index = index, columns = columns, aggfunc = aggfunc)
+
+  py_table <- tryCatch(
+    {
+      acroEnv$ac$pivot_table(data, values = values, index = index, columns = columns, aggfunc = aggfunc)
+    },
+    error = function(e) {
+      if (grepl("aggfunc", e$message, ignore.case = TRUE)) {
+        stop(
+          sprintf("Unsupported aggregation function provided: '%s'. Allowed functions are: mean, median, sum, std, count, mode.", aggfunc),
+          call. = FALSE
+        )
+      } else {
+        stop(e) # nocov
+      }
+    }
+  )
+
   table <- reticulate::py_to_r(py_table)
   return(table)
 }

tests/testthat/test-acro_crosstab.R

@@ -28,3 +28,44 @@ test_that("acro_crosstab works with margins", {
 
   expect_equal(unname(as.matrix(r_table)), unname(as.matrix(p_table)))
 })
+
+test_that("acro_crosstab works with aggregation function", {
+  # Creating the data frame with the specified values and row names
+  testthat::skip_on_cran()
+  expected_table <- data.frame(
+    convenient = c(3.25, 3.23, 3.25),
+    inconv = c(3.26, 3.26, 3.24)
+  )
+
+  # Assigning row names to the data frame
+  row.names(expected_table) <- c("not_recom", "priority", "recommended")
+
+  acro_init()
+  table <- acro_crosstab(index = nursery_data[, c("health")], columns = nursery_data[, c("finance")], values = nursery_data[, c("children")], aggfunc = "mean")
+  expect_equal(table[, -1, drop = FALSE], expected_table[, -1, drop = FALSE], tolerance = 0.01)
+})
+
+test_that("acro_crosstab throws an error for unsupported aggregation functions", {
+  acro_init()
+  expect_error(
+    acro_crosstab(
+      index = nursery_data$health,
+      columns = nursery_data$finance,
+      values = nursery_data$children,
+      aggfunc = "max"
+    ),
+    "Unsupported aggregation function provided"
+  )
+})
+
+test_that("acro_crosstab throws an error for missing values", {
+  acro_init()
+  expect_error(
+    acro_crosstab(
+      index = nursery_data$health,
+      columns = nursery_data$finance,
+      aggfunc = "mean"
+    ),
+    "If you pass an aggregation function to crosstab"
+  )
+})

tests/testthat/test-acro_pivot_table.R

@@ -19,3 +19,16 @@ test_that("acro_pivot_table works", {
   table <- acro_pivot_table(data = nursery_data, index = "parents", values = "children", aggfunc = list("mean", "std"))
   expect_equal(table[, -1, drop = FALSE], expected_table[, -1, drop = FALSE])
 })
+
+test_that("acro_pivot_table throws an error for unsupported aggregation functions", {
+  acro_init()
+  expect_error(
+    acro_pivot_table(
+      data = nursery_data,
+      index = nursery_data$parents,
+      values = nursery_data$children,
+      aggfunc = "max"
+    ),
+    "Unsupported aggregation function provided"
+  )
+})