Added basic translation of "find"

R/find.R

@@ -0,0 +1,9 @@
+#' @title Find indices and values of nonzero elements
+#' @description Emulates behavior of `find`
+find <- function(x) {
+    if (is.logical(x)) {
+        return(which(x))
+    } else {
+        return(which(x > 0))        
+    }
+}

man/find.Rd

@@ -0,0 +1,11 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/find.R
+\name{find}
+\alias{find}
+\title{Find indices and values of nonzero elements}
+\usage{
+find(x)
+}
+\description{
+Emulates behavior of `find`
+}

tests/testthat/test-convertedBaseFunctions.R

@@ -143,4 +143,12 @@ test_that("isempty works as expected", {
     expect_false(isempty(cat1))
     expect_true(isempty(cat2))
     expect_false(isempty(str1))
+})
+
+test_that("find works as expected", {
+    X <- matrix(c(1, 0, 2, 0, 1, 1, 0, 0, 4), 3, byrow=TRUE)
+    Y <- seq(1, 19, 2)
+    expect_equal(find(X), c(1, 5, 7, 8, 9))
+    expect_equal(find(!X), c(2, 3, 4, 6))
+    expect_equal(find(Y == 13), 7)
 })