Reorganization and improvements on matlab2r

R/matlab2r.R

@@ -1,13 +1,16 @@
 #' @title Convert Matlab function to R
 #' @description Performs basic syntax conversion from Matlab to R
 #' @param filename name of the file
-#' @param saveOutput if `TRUE`, `filename` is overwritten. Defaults to `FALSE`
+#' @param output can be "asis", "clean" (default) or "save"
+#' @param improve_formatting if `TRUE` (default), makes minor changes
+#' to conform to best-practice formatting conventions
 #' @return text converted to R, printed to screen or replacing input file
 #' @author Waldir Leoncio
 #' @importFrom utils write.table
 #' @export
-matlab2r <- function(filename, saveOutput = FALSE) {
-
+matlab2r <- function(
+	filename, output = "clean", improve_formatting=TRUE
+) {
 	# ======================================================== #
 	# Verification                                             #
 	# ======================================================== #
@@ -22,10 +25,18 @@ matlab2r <- function(filename, saveOutput = FALSE) {
 	# Replacing text                                           #
 	# ======================================================== #
 
+	# Uncommenting ------------------------------------------- #
+	txt <- gsub("^#\\s?(.+)", "\\1", txt)
+
 	# Function header ---------------------------------------- #
+	out <- gsub(
+		pattern     = "\\t*function (.+)\\s*=\\s*(.+)\\((.+)\\)",
+		replacement = "\treturn(\\1)",
+		x           = txt[1]
+	)
 	txt <- gsub(
-		pattern     = "function (.+)\\s+=\\s*(.+)\\((.+)\\)",
-		replacement = "\\2 <- function(\\3) { return(\\1)",
+		pattern     = "\\t*function (.+)\\s*=\\s*(.+)\\((.+)\\)",
+		replacement = "\\2 <- function(\\3) {",
 		x           = txt
 	)
 	txt <- gsub(
@@ -33,24 +44,45 @@ matlab2r <- function(filename, saveOutput = FALSE) {
 		replacement = "\\1 <- function(\\2) {",
 		x           = txt
 	)
-	# txt <- gsub("\\%\\s*(\\w+)", "# \\1", txt)
+
+	# Function body ------------------------------------------ #
+	txt <- gsub("(.+)\\.\\.\\.", "\\1", txt)
 	txt <- gsub(";", "", txt)
+
+	# Loops and if-statements
 	txt <- gsub("for (.+)=(.+)", "for (\\1 in \\2) {", txt)
-	txt <- gsub("end", "}", txt)
-	txt <- gsub("(.),(\\S)", "\\1, \\2", txt)
-	# TODO: replace forms like (:,:) with [, ] if they come before <-
-	# TODO: add argument to skip some of these rules
+	txt <- gsub("end$", "}", txt)
 	txt <- gsub("if (.+)", "if (\\1) {", txt) # FIXME: paste comments after {
 	txt <- gsub("else$", "} else {", txt)
 	txt <- gsub("elseif", "} else if", txt)
-	txt <- gsub("\\(~", "(!", txt)
 	txt <- gsub("while (.+)", "while \\1 {", txt)
-	## Math operators
-	txt <- gsub("(\\S)\\+(\\S)", "\\1 + \\2", txt)
-	txt <- gsub("(\\S)\\-(\\S)", "\\1 - \\2", txt)
-	txt <- gsub("(\\S)\\*(\\S)", "\\1 * \\2", txt)
-	# Returning converted code
-	if (!saveOutput) {
+
+	# MATLAB-equivalent functions in R
+	txt <- gsub("gamma_ln", "log_gamma", txt)
+
+	# Subsets ------------------------------------------------ #
+	txt <- gsub("([^\\(]+)\\((.+)\\)\\s?=(.+)", "\\1[\\2] <- \\3", txt)
+
+	# Formatting --------------------------------------------- #
+	if (improve_formatting) {
+		txt <- gsub("(.),(\\S)", "\\1, \\2", txt)
+		# Math operators
+		txt <- gsub("(\\S)\\+(\\S)", "\\1 + \\2", txt)
+		txt <- gsub("(\\S)\\-(\\S)", "\\1 - \\2", txt)
+		txt <- gsub("(\\S)\\*(\\S)", "\\1 * \\2", txt)
+		# Logic operators
+		txt <- gsub("\\(~", "(!", txt)
+		# Assignment
+		txt <- gsub("(.+)\\s?=\\s?(.+)", "\\1 <- \\2", txt)
+	}
+
+	# Adding output and end-of-file brace -------------------- #
+	txt <- append(txt, paste(out, "\n}"))
+
+	# Returning converted code ------------------------------- #
+	if (output == "asis") {
+		return(txt)
+	} else if (output == "clean") {
 		return(cat(txt, sep="\n"))
 	} else {
 		return(

man/matlab2r.Rd

@@ -4,12 +4,15 @@
 \alias{matlab2r}
 \title{Convert Matlab function to R}
 \usage{
-matlab2r(filename, saveOutput = FALSE)
+matlab2r(filename, output = "clean", improve_formatting = TRUE)
 }
 \arguments{
 \item{filename}{name of the file}
 
-\item{saveOutput}{if `TRUE`, `filename` is overwritten. Defaults to `FALSE`}
+\item{output}{can be "asis", "clean" (default) or "save"}
+
+\item{improve_formatting}{if `TRUE` (default), makes minor changes
+to conform to best-practice formatting conventions}
 }
 \value{
 text converted to R, printed to screen or replacing input file