From 0389de1aa3fa5d746f278d03e1901cb5c48e20c3 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Fri, 23 Mar 2018 09:03:24 +1100
Subject: [PATCH 01/18] rownames argument to as.matrix and as.data.frame

---
 R/data.table.R | 104 +++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 93 insertions(+), 11 deletions(-)

diff --git a/R/data.table.R b/R/data.table.R
index aad2d328b..c961256b8 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1859,17 +1859,58 @@ chmatch2 <- function(x, table, nomatch=NA_integer_) {
 #    x
 #}
 
-
-as.matrix.data.table <- function(x,...)
-{
-  dm <- dim(x)
-  cn <- names(x)
+as.matrix.data.table <- function(x, rownames, ...) {
+  rn <- NULL
+  rnc <- NULL
+  if (!missing(rownames)) { # Convert rownames to a column index if possible
+    if (is.null(rownames)) {
+      warning("rownames is NULL, ignoring rownames")
+    } else if (length(rownames) != 1) {
+      stop("rownames must be a single column in x")
+    } else if (is.na(rownames)) {
+      warning("rownames is NA, ignoring rownames")
+    } else if (is.logical(rownames) && !isTRUE(rownames)) {
+      warning("rownames is FALSE, ignoring rownames")
+    } else if (!(is.logical(rownames) || is.character(rownames) || is.numeric(rownames))) {
+      # E.g. because rownames is some sort of object that cant be converted to a column index
+      stop("rownames must be TRUE, a column index, or a column name in x")
+    } else {
+      if (is.logical(rownames) && isTRUE(rownames)) {
+        if (haskey(x)) { 
+          rownames <- key(x) 
+          if (length(rownames) > 1) {
+            warning("rownames is TRUE but multiple keys found in key(x), using first column instead")
+            rownames <- 1
+          }
+        } else { 
+          rownames <- 1
+        }
+      }
+      if (is.character(rownames)) { # Handles cases where rownames is a column name, or key(x) from TRUE
+        rnc <- chmatch(rownames, names(x))
+        if (is.na(rnc)) stop(rownames, " is not a column of x")
+      } else { # rownames is an index already
+        if (rownames < 1 || rownames > ncol(x))
+          stop("rownames is ", rownames, " which is outside the column number range [1,ncol=", ncol(x), "]")
+        rnc <- rownames
+      }
+    }
+  }
+  if (!is.null(rnc)) { # If there are rownames, extract and drop that column
+    rn <- x[, ..rnc][[1]]
+    dm <- dim(x) - c(0, 1)
+    cn <- names(x)[-rnc]
+    X <- x[, -rnc, with = FALSE]
+  } else {
+    dm <- dim(x) 
+    cn <- names(x) 
+    X <- x
+  }
   if (any(dm == 0L))
-    return(array(NA, dim = dm, dimnames = list(NULL, cn)))
+    return(array(NA, dim = dm, dimnames = list(rn, cn)))
   p <- dm[2L]
   n <- dm[1L]
   collabs <- as.list(cn)
-  X <- x
   class(X) <- NULL
   non.numeric <- non.atomic <- FALSE
   all.logical <- TRUE
@@ -1914,7 +1955,7 @@ as.matrix.data.table <- function(x,...)
   }
   X <- unlist(X, recursive = FALSE, use.names = FALSE)
   dim(X) <- c(n, length(X)/n)
-  dimnames(X) <- list(NULL, unlist(collabs, use.names = FALSE))
+  dimnames(X) <- list(rn, unlist(collabs, use.names = FALSE))
   X
 }
 
@@ -2006,10 +2047,51 @@ tail.data.table <- function(x, n=6L, ...) {
   `[<-.data.table`(x,j=name,value=value)  # important i is missing here
 }
 
-as.data.frame.data.table <- function(x, ...)
+as.data.frame.data.table <- function(x, rownames, ...)
 {
-  ans = copy(x)
-  setattr(ans,"row.names",.set_row_names(nrow(x)))   # since R 2.4.0, data.frames can have non-character row names
+  rnc <- NULL
+  if (!missing(rownames)) { # Convert rownames to a column index if possible
+    if (is.null(rownames)) {
+      warning("rownames is NULL, ignoring rownames")
+    } else if (length(rownames) != 1) {
+      stop("rownames must be a single column in x")
+    } else if (is.na(rownames)) {
+      warning("rownames is NA, ignoring rownames")
+    } else if (is.logical(rownames) && !isTRUE(rownames)) {
+      warning("rownames is FALSE, ignoring rownames")
+    } else if (!(is.logical(rownames) || is.character(rownames) || is.numeric(rownames))) {
+      # E.g. because rownames is some sort of object that cant be converted to a column index
+      stop("rownames must be TRUE, a column index, or a column name in x")
+    } else {
+      if (is.logical(rownames) && isTRUE(rownames)) {
+        if (haskey(x)) { 
+          rownames <- key(x) 
+          if (length(rownames) > 1) {
+            warning("rownames is TRUE but multiple keys found in key(x), using first column instead")
+            rownames <- 1
+          }
+        } else { 
+          rownames <- 1
+        }
+      }
+      if (is.character(rownames)) { # Handles cases where rownames is a column name, or key(x) from TRUE
+        rnc <- chmatch(rownames, names(x))
+        if (is.na(rnc)) stop(rownames, " is not a column of x")
+      } else { # rownames is an index already
+        if (rownames < 1 || rownames > ncol(x))
+          stop("rownames is ", rownames, " which is outside the column number range [1,ncol=", ncol(x), "]")
+        rnc <- rownames
+      }
+    }
+  }
+  if (!is.null(rnc)) { # If there are rownames, extract and drop that column
+    rn <- x[, ..rnc][[1]]
+    ans <- x[, -rnc, with = FALSE]
+    rownames(ans) <- rn # settatr(ans, "row.names", rn) only wokrs for character row names
+  } else {
+    ans = copy(x)
+    setattr(ans,"row.names",.set_row_names(nrow(x)))   # since R 2.4.0, data.frames can have non-character row names
+  }
   setattr(ans,"class","data.frame")
   setattr(ans,"sorted",NULL)  # remove so if you convert to df, do something, and convert back, it is not sorted
   setattr(ans,".internal.selfref",NULL)

From b1590ae43ddac3f4469220b3e82bce56aca6718a Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Fri, 23 Mar 2018 12:23:11 +1100
Subject: [PATCH 02/18] Added documentation

---
 man/as.data.frame.Rd | 66 ++++++++++++++++++++++++++++++++++++++++++++
 man/as.matrix.Rd     | 62 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 128 insertions(+)
 create mode 100644 man/as.data.frame.Rd
 create mode 100644 man/as.matrix.Rd

diff --git a/man/as.data.frame.Rd b/man/as.data.frame.Rd
new file mode 100644
index 000000000..c42779cd5
--- /dev/null
+++ b/man/as.data.frame.Rd
@@ -0,0 +1,66 @@
+\name{as.data.frame}
+\alias{as.data.frame}
+\alias{as.data.frame.data.table}
+\title{Convert a data.table to a data.frame}
+\description{
+Converts a \code{data.table} into a \code{data.frame}, optionally using one
+of the columns in the \code{data.table} as the \code{data.frame} \code{rownames}.
+
+If you do not need to use one of the columns as the \code{rownames}, use
+\code{\link{setDF}} to coerce a \code{data.table} to a \code{data.frame} 
+by reference (i.e. without making another copy in memory).
+}
+\usage{
+\method{as.data.frame}{data.table}(x, rownames, ...)}
+
+\arguments{
+\item{x}{a \code{data.table}}
+\item{rownames}{optional, a single column name or column index to use as 
+the \code{rownames} inthe returned \code{matrix}. If \code{TRUE} the
+\code{\link{key}} of the \code{data.table} will be used if it is a 
+single column, otherwise the first column in the \code{data.table} will
+be used.}
+\item{\dots}{additional arguments to be passed to or from methods.}
+}
+
+\details{
+\code{\link{as.data.frame}} is a generic function in base R. It dispatches to
+\code{as.data.frame.data.table} if its \code{x} argument is a \code{data.table}.
+
+The method for \code{data.table}s will create a copy of \code{x} with
+the \code{data.table} class attributes removed. An additional argument 
+\code{rownames} is provided for \code{as.data.frame.data.table} that 
+allows a single column to be removed from \code{x} to be used as the 
+\code{\link{rownames}} of the resulting \code{data.frame}. An example
+of where this is useful is where a function from another package expects
+the data stored in the first column of \code{x} to be the \code{rownames}
+of the data frame for the purposes of subsetting or matching rows in 
+its internal workings.
+
+If you do not wish to keep a copy of \code{x} as a \code{data.table} and 
+do not need to use the \code{rownames} argument you should use the
+\code{\link{setDF}} function instead, which will coerce \code{x} to a 
+\code{data.frame} by reference (i.e. without making another copy in memory).
+}
+
+\value{
+A new \code{data.frame} containing the contents of \code{x}.
+}
+
+\seealso{
+\code{\link{data.table}}, \code{\link{as.data.frame}}, \code{\link{setDF}}
+}
+
+\examples{
+(dt1 <- data.table(A = letters[1:10], X = 1:10, Y = 11:20))
+as.data.frame(dt1)
+as.data.frame(dt1, rownames = "A")
+as.data.frame(dt1, rownames = 1)
+as.data.frame(dt1, rownames = TRUE)
+
+(dt1 <- data.table(A = letters[1:10], X = 1:10, Y = 11:20))
+setkey(dt1, A)
+as.data.frame(dt1, rownames = TRUE)
+
+setDF(dt1) # dt1 is a data.frame now
+}
diff --git a/man/as.matrix.Rd b/man/as.matrix.Rd
new file mode 100644
index 000000000..5e12239d9
--- /dev/null
+++ b/man/as.matrix.Rd
@@ -0,0 +1,62 @@
+\name{as.matrix}
+\alias{as.matrix}
+\alias{as.matrix.data.table}
+\title{Convert a data.table to a matrix}
+\description{
+Converts a \code{data.table} into a \code{matrix}, optionally using one
+of the columns in the \code{data.table} as the \code{matrix} \code{rownames}.
+}
+\usage{
+\method{as.matrix}{data.table}(x, rownames, ...)}
+
+\arguments{
+\item{x}{a \code{data.table}}
+\item{rownames}{optional, a single column name or column index to use as 
+the \code{rownames} inthe returned \code{matrix}. If \code{TRUE} the
+\code{\link{key}} of the \code{data.table} will be used if it is a 
+single column, otherwise the first column in the \code{data.table} will
+be used.}
+\item{\dots}{additional arguments to be passed to or from methods.}
+}
+
+\details{
+\code{\link{as.matrix}} is a generic function in base R. It dispatches to
+\code{as.matrix.data.table} if its \code{x} argument is a \code{data.table}.
+
+The method for \code{data.table}s will return a character matrix if there 
+are only atomic columns and any non-(numeric/logical/complex) column, 
+applying \code{\link{as.vector}} to factors and \code{\link{format}} to other 
+non-character columns. Otherwise, the usual coercion hierarchy (logical < 
+integer < double < complex) will be used, e.g., all-logical data frames 
+will be coerced to a logical matrix, mixed logical-integer will give an 
+integer matrix, etc.
+
+An additional argument \code{rownames} is provided for \code{as.matrix.data.table}
+to facilitate conversions to matrices where the \code{\link{rownames}} are stored
+in a single column of \code{x}, e.g. the first column after using 
+\code{\link{dcast.data.table}}.
+}
+
+\value{
+A new \code{matrix} containing the contents of \code{x}.
+}
+
+\seealso{
+\code{\link{data.table}}, \code{\link{as.matrix}}, \code{\link{data.matrix}}
+\code{\link{array}}
+}
+
+\examples{
+(dt1 <- data.table(A = letters[1:10], X = 1:10, Y = 11:20))
+as.matrix(dt1) # character matrix
+as.matrix(dt1, rownames = "A")
+as.matrix(dt1, rownames = 1)
+as.matrix(dt1, rownames = TRUE)
+
+(dt1 <- data.table(A = letters[1:10], X = 1:10, Y = 11:20))
+setkey(dt1, A)
+as.matrix(dt1, rownames = TRUE)
+}
+
+\keyword{ array }
+

From 1323be04461cb9b808d80d52c1dbb52c440a3a9f Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Fri, 23 Mar 2018 14:33:47 +1100
Subject: [PATCH 03/18] some unit tests

---
 inst/tests/tests.Rraw | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
index b4888c9e3..f21edca16 100644
--- a/inst/tests/tests.Rraw
+++ b/inst/tests/tests.Rraw
@@ -11522,6 +11522,24 @@ test(1893.2, print(DF), output=txt)
 txt = 'A,B\n109,MT\n7,N\n11,NA\n41,NB\n60,ND\n1,""\n2,\n3,"NA"\n4,NA\n'
 test(1893.3, print(fread(txt,na.strings="")), output="A    B\n1: 109   MT\n2:   7    N\n3:  11   NA\n4:  41   NB\n5:  60   ND\n6:   1     \n7:   2 <NA>\n8:   3   NA\n9:   4   NA")
 
+# Allow column to be used as rownames when converting to matrix or data.frame # 2702
+DT = data.table(id = letters[1:4], X = 1:4, Y = 5:8)
+mat <- matrix(1:8, ncol = 2, dimnames=list(letters[1:4], c("X", "Y")))
+test(2702.1, as.matrix(DT, 1), mat)
+test(2702.2, as.matrix(DT, "id"), mat)
+test(2702.3, as.matrix(DT, TRUE), mat)
+setkey(DT, id)
+test(2702.4, as.matrix(DT, TRUE), mat)
+
+DT = data.table(id = letters[1:4], X = 1:4, Y = 5:8)
+DF <- data.frame(X = 1:4, Y = 5:8)
+rownames(DF) <- letters[1:4]
+test(2702.5, as.data.frame(DT, 1), DF)
+test(2702.6, as.data.frame(DT, "id"), DF)
+test(2702.7, as.data.frame(DT, TRUE), DF)
+setkey(DT, id)
+test(2702.8, as.data.frame(DT, TRUE), DF)
+
 ###################################
 #  Add new tests above this line  #
 ###################################

From ddaeb6ac026d5362653fd184bfe21a027eb01be5 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Fri, 23 Mar 2018 14:39:35 +1100
Subject: [PATCH 04/18] added news

---
 NEWS.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/NEWS.md b/NEWS.md
index fe9b2ab7f..9f41a12aa 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -103,6 +103,8 @@ Thanks to @MichaelChirico for reporting and to @MarkusBonsch for the implementat
 
 17. `update.dev.pkg` is new function to update package from development repository, it will download package sources only when newer commit is available in repository. `data.table::update.dev.pkg()` defaults updates `data.table`, but any package can be used.
 
+18. `as.matrix.data.table` and `as.data.frame.data.table` methods now have an additional `rownames` argument allowing for a single column to be used as the `rownames` after conversion to a `matrix` or `data.frame` resepctively. Thanks to @sritchie73 for the suggestion, use cases, [#2692](https://github.com/Rdatatable/data.table/issues/2692) and implementation [PR#2702](https://github.com/Rdatatable/data.table/pull/2702) and @MichaelChirico for additional use cases.
+
 #### BUG FIXES
 
 1. The new quote rules handles this single field `"Our Stock Screen Delivers an Israeli Software Company (MNDO, CTCH)<\/a> SmallCapInvestor.com - Thu, May 19, 2011 10:02 AM EDT<\/cite><\/div>Yesterday in \""Google, But for Finding

From 0ab7e4f980ad9a100cc044c03f5aaadb7b232c66 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sat, 24 Mar 2018 10:03:53 +1100
Subject: [PATCH 05/18] Resolve CRAN notes about global variable bindings

---
 R/data.table.R | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/R/data.table.R b/R/data.table.R
index c961256b8..c86fe645c 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1897,7 +1897,7 @@ as.matrix.data.table <- function(x, rownames, ...) {
     }
   }
   if (!is.null(rnc)) { # If there are rownames, extract and drop that column
-    rn <- x[, ..rnc][[1]]
+    rn <- x[[rnc]]
     dm <- dim(x) - c(0, 1)
     cn <- names(x)[-rnc]
     X <- x[, -rnc, with = FALSE]
@@ -2085,7 +2085,7 @@ as.data.frame.data.table <- function(x, rownames, ...)
     }
   }
   if (!is.null(rnc)) { # If there are rownames, extract and drop that column
-    rn <- x[, ..rnc][[1]]
+    rn <- x[[rnc]]
     ans <- x[, -rnc, with = FALSE]
     rownames(ans) <- rn # settatr(ans, "row.names", rn) only wokrs for character row names
   } else {

From 8477788b02f254b899d8c74d645fc77fe8af2af9 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sat, 24 Mar 2018 10:17:55 +1100
Subject: [PATCH 06/18] Reverted as.data.frame.data.table

---
 NEWS.md               |  2 +-
 R/data.table.R        | 47 ++----------------------------
 inst/tests/tests.Rraw | 11 +-------
 man/as.data.frame.Rd  | 66 -------------------------------------------
 4 files changed, 5 insertions(+), 121 deletions(-)
 delete mode 100644 man/as.data.frame.Rd

diff --git a/NEWS.md b/NEWS.md
index 9f41a12aa..1a47b1f66 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -103,7 +103,7 @@ Thanks to @MichaelChirico for reporting and to @MarkusBonsch for the implementat
 
 17. `update.dev.pkg` is new function to update package from development repository, it will download package sources only when newer commit is available in repository. `data.table::update.dev.pkg()` defaults updates `data.table`, but any package can be used.
 
-18. `as.matrix.data.table` and `as.data.frame.data.table` methods now have an additional `rownames` argument allowing for a single column to be used as the `rownames` after conversion to a `matrix` or `data.frame` resepctively. Thanks to @sritchie73 for the suggestion, use cases, [#2692](https://github.com/Rdatatable/data.table/issues/2692) and implementation [PR#2702](https://github.com/Rdatatable/data.table/pull/2702) and @MichaelChirico for additional use cases.
+18. `as.matrix.data.table` method now has an additional `rownames` argument allowing for a single column to be used as the `rownames` after conversion to a `matrix`. Thanks to @sritchie73 for the suggestion, use cases, [#2692](https://github.com/Rdatatable/data.table/issues/2692) and implementation [PR#2702](https://github.com/Rdatatable/data.table/pull/2702) and @MichaelChirico for additional use cases.
 
 #### BUG FIXES
 
diff --git a/R/data.table.R b/R/data.table.R
index c86fe645c..78e6f02f9 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -2047,51 +2047,10 @@ tail.data.table <- function(x, n=6L, ...) {
   `[<-.data.table`(x,j=name,value=value)  # important i is missing here
 }
 
-as.data.frame.data.table <- function(x, rownames, ...)
+as.data.frame.data.table <- function(x, ...)
 {
-  rnc <- NULL
-  if (!missing(rownames)) { # Convert rownames to a column index if possible
-    if (is.null(rownames)) {
-      warning("rownames is NULL, ignoring rownames")
-    } else if (length(rownames) != 1) {
-      stop("rownames must be a single column in x")
-    } else if (is.na(rownames)) {
-      warning("rownames is NA, ignoring rownames")
-    } else if (is.logical(rownames) && !isTRUE(rownames)) {
-      warning("rownames is FALSE, ignoring rownames")
-    } else if (!(is.logical(rownames) || is.character(rownames) || is.numeric(rownames))) {
-      # E.g. because rownames is some sort of object that cant be converted to a column index
-      stop("rownames must be TRUE, a column index, or a column name in x")
-    } else {
-      if (is.logical(rownames) && isTRUE(rownames)) {
-        if (haskey(x)) { 
-          rownames <- key(x) 
-          if (length(rownames) > 1) {
-            warning("rownames is TRUE but multiple keys found in key(x), using first column instead")
-            rownames <- 1
-          }
-        } else { 
-          rownames <- 1
-        }
-      }
-      if (is.character(rownames)) { # Handles cases where rownames is a column name, or key(x) from TRUE
-        rnc <- chmatch(rownames, names(x))
-        if (is.na(rnc)) stop(rownames, " is not a column of x")
-      } else { # rownames is an index already
-        if (rownames < 1 || rownames > ncol(x))
-          stop("rownames is ", rownames, " which is outside the column number range [1,ncol=", ncol(x), "]")
-        rnc <- rownames
-      }
-    }
-  }
-  if (!is.null(rnc)) { # If there are rownames, extract and drop that column
-    rn <- x[[rnc]]
-    ans <- x[, -rnc, with = FALSE]
-    rownames(ans) <- rn # settatr(ans, "row.names", rn) only wokrs for character row names
-  } else {
-    ans = copy(x)
-    setattr(ans,"row.names",.set_row_names(nrow(x)))   # since R 2.4.0, data.frames can have non-character row names
-  }
+  ans = copy(x)
+  setattr(ans,"row.names",.set_row_names(nrow(x)))   # since R 2.4.0, data.frames can have non-character row names
   setattr(ans,"class","data.frame")
   setattr(ans,"sorted",NULL)  # remove so if you convert to df, do something, and convert back, it is not sorted
   setattr(ans,".internal.selfref",NULL)
diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
index f21edca16..1fe2bb20b 100644
--- a/inst/tests/tests.Rraw
+++ b/inst/tests/tests.Rraw
@@ -11522,7 +11522,7 @@ test(1893.2, print(DF), output=txt)
 txt = 'A,B\n109,MT\n7,N\n11,NA\n41,NB\n60,ND\n1,""\n2,\n3,"NA"\n4,NA\n'
 test(1893.3, print(fread(txt,na.strings="")), output="A    B\n1: 109   MT\n2:   7    N\n3:  11   NA\n4:  41   NB\n5:  60   ND\n6:   1     \n7:   2 <NA>\n8:   3   NA\n9:   4   NA")
 
-# Allow column to be used as rownames when converting to matrix or data.frame # 2702
+# Allow column to be used as rownames when converting to matrix # 2702
 DT = data.table(id = letters[1:4], X = 1:4, Y = 5:8)
 mat <- matrix(1:8, ncol = 2, dimnames=list(letters[1:4], c("X", "Y")))
 test(2702.1, as.matrix(DT, 1), mat)
@@ -11531,15 +11531,6 @@ test(2702.3, as.matrix(DT, TRUE), mat)
 setkey(DT, id)
 test(2702.4, as.matrix(DT, TRUE), mat)
 
-DT = data.table(id = letters[1:4], X = 1:4, Y = 5:8)
-DF <- data.frame(X = 1:4, Y = 5:8)
-rownames(DF) <- letters[1:4]
-test(2702.5, as.data.frame(DT, 1), DF)
-test(2702.6, as.data.frame(DT, "id"), DF)
-test(2702.7, as.data.frame(DT, TRUE), DF)
-setkey(DT, id)
-test(2702.8, as.data.frame(DT, TRUE), DF)
-
 ###################################
 #  Add new tests above this line  #
 ###################################
diff --git a/man/as.data.frame.Rd b/man/as.data.frame.Rd
deleted file mode 100644
index c42779cd5..000000000
--- a/man/as.data.frame.Rd
+++ /dev/null
@@ -1,66 +0,0 @@
-\name{as.data.frame}
-\alias{as.data.frame}
-\alias{as.data.frame.data.table}
-\title{Convert a data.table to a data.frame}
-\description{
-Converts a \code{data.table} into a \code{data.frame}, optionally using one
-of the columns in the \code{data.table} as the \code{data.frame} \code{rownames}.
-
-If you do not need to use one of the columns as the \code{rownames}, use
-\code{\link{setDF}} to coerce a \code{data.table} to a \code{data.frame} 
-by reference (i.e. without making another copy in memory).
-}
-\usage{
-\method{as.data.frame}{data.table}(x, rownames, ...)}
-
-\arguments{
-\item{x}{a \code{data.table}}
-\item{rownames}{optional, a single column name or column index to use as 
-the \code{rownames} inthe returned \code{matrix}. If \code{TRUE} the
-\code{\link{key}} of the \code{data.table} will be used if it is a 
-single column, otherwise the first column in the \code{data.table} will
-be used.}
-\item{\dots}{additional arguments to be passed to or from methods.}
-}
-
-\details{
-\code{\link{as.data.frame}} is a generic function in base R. It dispatches to
-\code{as.data.frame.data.table} if its \code{x} argument is a \code{data.table}.
-
-The method for \code{data.table}s will create a copy of \code{x} with
-the \code{data.table} class attributes removed. An additional argument 
-\code{rownames} is provided for \code{as.data.frame.data.table} that 
-allows a single column to be removed from \code{x} to be used as the 
-\code{\link{rownames}} of the resulting \code{data.frame}. An example
-of where this is useful is where a function from another package expects
-the data stored in the first column of \code{x} to be the \code{rownames}
-of the data frame for the purposes of subsetting or matching rows in 
-its internal workings.
-
-If you do not wish to keep a copy of \code{x} as a \code{data.table} and 
-do not need to use the \code{rownames} argument you should use the
-\code{\link{setDF}} function instead, which will coerce \code{x} to a 
-\code{data.frame} by reference (i.e. without making another copy in memory).
-}
-
-\value{
-A new \code{data.frame} containing the contents of \code{x}.
-}
-
-\seealso{
-\code{\link{data.table}}, \code{\link{as.data.frame}}, \code{\link{setDF}}
-}
-
-\examples{
-(dt1 <- data.table(A = letters[1:10], X = 1:10, Y = 11:20))
-as.data.frame(dt1)
-as.data.frame(dt1, rownames = "A")
-as.data.frame(dt1, rownames = 1)
-as.data.frame(dt1, rownames = TRUE)
-
-(dt1 <- data.table(A = letters[1:10], X = 1:10, Y = 11:20))
-setkey(dt1, A)
-as.data.frame(dt1, rownames = TRUE)
-
-setDF(dt1) # dt1 is a data.frame now
-}

From ac52d9ada9d8a0e970222ba95e5170133a597988 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sat, 24 Mar 2018 11:41:45 +1100
Subject: [PATCH 07/18] Unit tests for errors and warnings

---
 inst/tests/tests.Rraw | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
index 1fe2bb20b..3897a731f 100644
--- a/inst/tests/tests.Rraw
+++ b/inst/tests/tests.Rraw
@@ -11530,6 +11530,19 @@ test(2702.2, as.matrix(DT, "id"), mat)
 test(2702.3, as.matrix(DT, TRUE), mat)
 setkey(DT, id)
 test(2702.4, as.matrix(DT, TRUE), mat)
+# errors
+test(2702.5, as.matrix(DT, -1), error="rownames is -1 which is outside the column number range")
+test(2702.6, as.matrix(DT, "Z"), error="Z is not a column of x")
+test(2702.7, as.matrix(DT, c(1,2)), error="rownames must be a single column of x")
+test(2702.8, as.matrix(DT, complex(1)), error="rownames must be TRUE, a column index, or a column name in x")
+# warnings
+mat2 <- matrix(c(letters[1:4], 1:8), ncol=3, dimnames=list(NULL, c("id", "X", "Y")))
+test(2702.9, as.matrix(DT, NA), mat2, warning="rownames is NA, ignoring rownames")
+test(2702.10, as.matrix(DT, NULL), mat2, warning="rownames is NULL, ignoring rownames")
+test(2702.11, as.matrix(DT, FALSE), mat2, warning="rownames is FALSE, ignoring rownames")
+setkey(DT, id, X)
+test(2702.12, as.matrix(DT, TRUE), mat, warning="rownames is TRUE but multiple keys found in key(x), using first column instead")
+
 
 ###################################
 #  Add new tests above this line  #

From b9eab65c03c59900bdc38e8be87633575f1670ca Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sat, 24 Mar 2018 12:15:38 +1100
Subject: [PATCH 08/18] Fixed error message in tests and test increment numbers

---
 inst/tests/tests.Rraw | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
index 3897a731f..b26668672 100644
--- a/inst/tests/tests.Rraw
+++ b/inst/tests/tests.Rraw
@@ -11525,19 +11525,19 @@ test(1893.3, print(fread(txt,na.strings="")), output="A    B\n1: 109   MT\n2:
 # Allow column to be used as rownames when converting to matrix # 2702
 DT = data.table(id = letters[1:4], X = 1:4, Y = 5:8)
 mat <- matrix(1:8, ncol = 2, dimnames=list(letters[1:4], c("X", "Y")))
-test(2702.1, as.matrix(DT, 1), mat)
-test(2702.2, as.matrix(DT, "id"), mat)
-test(2702.3, as.matrix(DT, TRUE), mat)
+test(2702.01, as.matrix(DT, 1), mat)
+test(2702.02, as.matrix(DT, "id"), mat)
+test(2702.03, as.matrix(DT, TRUE), mat)
 setkey(DT, id)
-test(2702.4, as.matrix(DT, TRUE), mat)
+test(2702.04, as.matrix(DT, TRUE), mat)
 # errors
-test(2702.5, as.matrix(DT, -1), error="rownames is -1 which is outside the column number range")
-test(2702.6, as.matrix(DT, "Z"), error="Z is not a column of x")
-test(2702.7, as.matrix(DT, c(1,2)), error="rownames must be a single column of x")
-test(2702.8, as.matrix(DT, complex(1)), error="rownames must be TRUE, a column index, or a column name in x")
-# warnings
+test(2702.05, as.matrix(DT, -1), error="rownames is -1 which is outside the column number range")
+test(2702.06, as.matrix(DT, "Z"), error="Z is not a column of x")
+test(2702.07, as.matrix(DT, c(1,2)), error="rownames must be a single column in x")
+test(2702.08, as.matrix(DT, complex(1)), error="rownames must be TRUE, a column index, or a column name in x")
+# warningsi
 mat2 <- matrix(c(letters[1:4], 1:8), ncol=3, dimnames=list(NULL, c("id", "X", "Y")))
-test(2702.9, as.matrix(DT, NA), mat2, warning="rownames is NA, ignoring rownames")
+test(2702.09, as.matrix(DT, NA), mat2, warning="rownames is NA, ignoring rownames")
 test(2702.10, as.matrix(DT, NULL), mat2, warning="rownames is NULL, ignoring rownames")
 test(2702.11, as.matrix(DT, FALSE), mat2, warning="rownames is FALSE, ignoring rownames")
 setkey(DT, id, X)

From 11da1448c2f98c761115add34e0b0b41e2632822 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sun, 25 Mar 2018 17:52:25 +1100
Subject: [PATCH 09/18] Removed with=FALSE

---
 R/data.table.R | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/R/data.table.R b/R/data.table.R
index 5e76e4678..f30d94093 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1918,11 +1918,13 @@ as.matrix.data.table <- function(x, rownames, ...) {
       }
     }
   }
-  if (!is.null(rnc)) { # If there are rownames, extract and drop that column
+  # If the rownames argument has been used, and is a single column,
+  # extract that column's index (rnc) and drop it from x
+  if (!is.null(rnc)) { 
     rn <- x[[rnc]]
     dm <- dim(x) - c(0, 1)
     cn <- names(x)[-rnc]
-    X <- x[, -rnc, with = FALSE]
+    X <- x[, .SD, .SDcols = cn]
   } else {
     dm <- dim(x) 
     cn <- names(x) 

From 5b4bca72324cebdafe87cb4750c6c3ade99259d1 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sun, 25 Mar 2018 18:10:38 +1100
Subject: [PATCH 10/18] Enhanced clarity of an error check

---
 R/data.table.R | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/R/data.table.R b/R/data.table.R
index f30d94093..4b593f2e2 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1891,7 +1891,7 @@ as.matrix.data.table <- function(x, rownames, ...) {
       stop("rownames must be a single column in x")
     } else if (is.na(rownames)) {
       warning("rownames is NA, ignoring rownames")
-    } else if (is.logical(rownames) && !isTRUE(rownames)) {
+    } else if (identical(rownames, FALSE)) {
       warning("rownames is FALSE, ignoring rownames")
     } else if (!(is.logical(rownames) || is.character(rownames) || is.numeric(rownames))) {
       # E.g. because rownames is some sort of object that cant be converted to a column index

From c5ae94b4bced6399bde4e837589cc9454eac19e0 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sun, 25 Mar 2018 18:16:49 +1100
Subject: [PATCH 11/18] replaced isTRUE

---
 R/data.table.R | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/R/data.table.R b/R/data.table.R
index 4b593f2e2..75860e730 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1897,7 +1897,7 @@ as.matrix.data.table <- function(x, rownames, ...) {
       # E.g. because rownames is some sort of object that cant be converted to a column index
       stop("rownames must be TRUE, a column index, or a column name in x")
     } else {
-      if (is.logical(rownames) && isTRUE(rownames)) {
+      if (identical(rownames, TRUE)) {
         if (haskey(x)) { 
           rownames <- key(x) 
           if (length(rownames) > 1) {

From f07b813296adda4118197b46062b5da27571c634 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sun, 25 Mar 2018 18:37:05 +1100
Subject: [PATCH 12/18] Vector of rownames may be used in as.matrix

---
 R/data.table.R        |  8 ++++++--
 inst/tests/tests.Rraw | 22 ++++++++++++----------
 man/as.matrix.Rd      |  5 +++--
 3 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/R/data.table.R b/R/data.table.R
index 75860e730..3bc2b5771 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1887,15 +1887,19 @@ as.matrix.data.table <- function(x, rownames, ...) {
   if (!missing(rownames)) { # Convert rownames to a column index if possible
     if (is.null(rownames)) {
       warning("rownames is NULL, ignoring rownames")
+    } else if (length(rownames) == nrow(x)) {
+      # rownames argument is a vector of row names, no column in x to drop.
+      rn <- rownames
+      rnc <- NULL 
     } else if (length(rownames) != 1) {
-      stop("rownames must be a single column in x")
+      stop("rownames must be a single column in x or a vector of row names of length nrow(x)")
     } else if (is.na(rownames)) {
       warning("rownames is NA, ignoring rownames")
     } else if (identical(rownames, FALSE)) {
       warning("rownames is FALSE, ignoring rownames")
     } else if (!(is.logical(rownames) || is.character(rownames) || is.numeric(rownames))) {
       # E.g. because rownames is some sort of object that cant be converted to a column index
-      stop("rownames must be TRUE, a column index, or a column name in x")
+      stop("rownames must be TRUE, a column index, a column name in x, or a vector of row names")
     } else {
       if (identical(rownames, TRUE)) {
         if (haskey(x)) { 
diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
index 2541ebb5b..b15443ee4 100644
--- a/inst/tests/tests.Rraw
+++ b/inst/tests/tests.Rraw
@@ -11547,23 +11547,25 @@ test(1894.12, DT[, sum(y)*..z], error="..z in j is looking for z in calling scop
 # Allow column to be used as rownames when converting to matrix # 1895
 DT = data.table(id = letters[1:4], X = 1:4, Y = 5:8)
 mat <- matrix(1:8, ncol = 2, dimnames=list(letters[1:4], c("X", "Y")))
+mat2 <- matrix(c(letters[1:4], 1:8), ncol=3, dimnames=list(NULL, c("id", "X", "Y")))
+mat3 <- matrix(c(letters[1:4], 1:8), ncol=3, dimnames=list(1:4, c("id", "X", "Y")))
 test(1895.01, as.matrix(DT, 1), mat)
 test(1895.02, as.matrix(DT, "id"), mat)
 test(1895.03, as.matrix(DT, TRUE), mat)
 setkey(DT, id)
 test(1895.04, as.matrix(DT, TRUE), mat)
+test(1895.05, as.matrix(DT, 1:4), mat3)
 # errors
-test(1895.05, as.matrix(DT, -1), error="rownames is -1 which is outside the column number range")
-test(1895.06, as.matrix(DT, "Z"), error="Z is not a column of x")
-test(1895.07, as.matrix(DT, c(1,2)), error="rownames must be a single column in x")
-test(1895.08, as.matrix(DT, complex(1)), error="rownames must be TRUE, a column index, or a column name in x")
-# warningsi
-mat2 <- matrix(c(letters[1:4], 1:8), ncol=3, dimnames=list(NULL, c("id", "X", "Y")))
-test(1895.09, as.matrix(DT, NA), mat2, warning="rownames is NA, ignoring rownames")
-test(1895.10, as.matrix(DT, NULL), mat2, warning="rownames is NULL, ignoring rownames")
-test(1895.11, as.matrix(DT, FALSE), mat2, warning="rownames is FALSE, ignoring rownames")
+test(1895.06, as.matrix(DT, -1), error="rownames is -1 which is outside the column number range")
+test(1895.07, as.matrix(DT, "Z"), error="Z is not a column of x")
+test(1895.08, as.matrix(DT, c(1,2)), error="rownames must be a single column in x or a vector of row names of length nrow(x)")
+test(1895.09, as.matrix(DT, complex(1)), error="rownames must be TRUE, a column index, a column name in x, or a vector of row names")
+# warnings
+test(1895.10, as.matrix(DT, NA), mat2, warning="rownames is NA, ignoring rownames")
+test(1895.11, as.matrix(DT, NULL), mat2, warning="rownames is NULL, ignoring rownames")
+test(1895.12, as.matrix(DT, FALSE), mat2, warning="rownames is FALSE, ignoring rownames")
 setkey(DT, id, X)
-test(1895.12, as.matrix(DT, TRUE), mat, warning="rownames is TRUE but multiple keys found in key(x), using first column instead")
+test(1895.13, as.matrix(DT, TRUE), mat, warning="rownames is TRUE but multiple keys found in key(x), using first column instead")
 
 
 ###################################
diff --git a/man/as.matrix.Rd b/man/as.matrix.Rd
index 5e12239d9..f93f3ba89 100644
--- a/man/as.matrix.Rd
+++ b/man/as.matrix.Rd
@@ -12,10 +12,11 @@ of the columns in the \code{data.table} as the \code{matrix} \code{rownames}.
 \arguments{
 \item{x}{a \code{data.table}}
 \item{rownames}{optional, a single column name or column index to use as 
-the \code{rownames} inthe returned \code{matrix}. If \code{TRUE} the
+the \code{rownames} in the returned \code{matrix}. If \code{TRUE} the
 \code{\link{key}} of the \code{data.table} will be used if it is a 
 single column, otherwise the first column in the \code{data.table} will
-be used.}
+be used. Alternative a vector of length \code{nrow(x)} to assign as the
+row names of the returned \code{matrix}.}
 \item{\dots}{additional arguments to be passed to or from methods.}
 }
 

From 3d4681c684643b02a24daff1aeced0ccf4cfb215 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sun, 25 Mar 2018 20:31:00 +1100
Subject: [PATCH 13/18] Fixed number in tests to reflect PR

---
 inst/tests/tests.Rraw | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
index b15443ee4..a1a6ed06f 100644
--- a/inst/tests/tests.Rraw
+++ b/inst/tests/tests.Rraw
@@ -11544,7 +11544,7 @@ test(1894.11, DT[, sum(z)*..z], 72L)
 setnames(DT, "z", "..z")
 test(1894.12, DT[, sum(y)*..z], error="..z in j is looking for z in calling scope, but a column '..z' exists. Column names should not start with ..")
 
-# Allow column to be used as rownames when converting to matrix # 1895
+# Allow column to be used as rownames when converting to matrix #2702
 DT = data.table(id = letters[1:4], X = 1:4, Y = 5:8)
 mat <- matrix(1:8, ncol = 2, dimnames=list(letters[1:4], c("X", "Y")))
 mat2 <- matrix(c(letters[1:4], 1:8), ncol=3, dimnames=list(NULL, c("id", "X", "Y")))

From d9a4a54dbde72bb6a663e2ee4cde3888715ff0eb Mon Sep 17 00:00:00 2001
From: Michael Chirico <michaelchirico4@gmail.com>
Date: Tue, 27 Mar 2018 23:13:26 +0800
Subject: [PATCH 14/18] mainly cosmetic changes

(hopefully no typos; on browser)
---
 R/data.table.R | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/R/data.table.R b/R/data.table.R
index 3bc2b5771..a2b7f1697 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1891,33 +1891,34 @@ as.matrix.data.table <- function(x, rownames, ...) {
       # rownames argument is a vector of row names, no column in x to drop.
       rn <- rownames
       rnc <- NULL 
-    } else if (length(rownames) != 1) {
-      stop("rownames must be a single column in x or a vector of row names of length nrow(x)")
+    } else if (length(rownames) != 1L) {
+      stop(sprintf("rownames must be a single column in x or a vector of row names of length nrow(x)=%d", nrow(x)))
     } else if (is.na(rownames)) {
       warning("rownames is NA, ignoring rownames")
     } else if (identical(rownames, FALSE)) {
       warning("rownames is FALSE, ignoring rownames")
     } else if (!(is.logical(rownames) || is.character(rownames) || is.numeric(rownames))) {
-      # E.g. because rownames is some sort of object that cant be converted to a column index
+      # E.g. because rownames is some sort of object that can't be converted to a column index
       stop("rownames must be TRUE, a column index, a column name in x, or a vector of row names")
-    } else {
+    } else { # Handles cases where rownames is a column name, or key(x) from TRUE
       if (identical(rownames, TRUE)) {
         if (haskey(x)) { 
           rownames <- key(x) 
-          if (length(rownames) > 1) {
-            warning("rownames is TRUE but multiple keys found in key(x), using first column instead")
-            rownames <- 1
+          if (length(rownames) > 1L) {
+            warning(sprintf("rownames is TRUE but multiple keys [%s] found for x; defaulting to first key column [%s]",
+                            paste(rownames, collapse = ','), rownames[1L]))
+            rownames <- 1L
           }
         } else { 
-          rownames <- 1
+          rownames <- 1L
         }
       }
-      if (is.character(rownames)) { # Handles cases where rownames is a column name, or key(x) from TRUE
+      if (is.character(rownames)) { 
         rnc <- chmatch(rownames, names(x))
         if (is.na(rnc)) stop(rownames, " is not a column of x")
       } else { # rownames is an index already
-        if (rownames < 1 || rownames > ncol(x))
-          stop("rownames is ", rownames, " which is outside the column number range [1,ncol=", ncol(x), "]")
+        if (rownames < 1L || rownames > ncol(x))
+          stop(sprintf("rownames is %s which is outside the column number range [1,ncol=%d]", rownames, ncol(x)))
         rnc <- rownames
       }
     }

From de48d84cbed34498cfc6b7bd3346db7bb567df17 Mon Sep 17 00:00:00 2001
From: Michael Chirico <michaelchirico4@gmail.com>
Date: Tue, 27 Mar 2018 23:15:44 +0800
Subject: [PATCH 15/18] typo (rownames is integer not string here)

---
 R/data.table.R | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/R/data.table.R b/R/data.table.R
index a2b7f1697..4ece7ec27 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1918,7 +1918,7 @@ as.matrix.data.table <- function(x, rownames, ...) {
         if (is.na(rnc)) stop(rownames, " is not a column of x")
       } else { # rownames is an index already
         if (rownames < 1L || rownames > ncol(x))
-          stop(sprintf("rownames is %s which is outside the column number range [1,ncol=%d]", rownames, ncol(x)))
+          stop(sprintf("rownames is %d which is outside the column number range [1,ncol=%d]", rownames, ncol(x)))
         rnc <- rownames
       }
     }

From 895554e6f23d3fc9fd82e091985a6fe8fd7fdfe5 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sun, 1 Apr 2018 15:56:11 +1000
Subject: [PATCH 16/18] NULL, FALSE, and NA now passthrough instead of warning

---
 R/data.table.R        | 14 ++++----------
 inst/tests/tests.Rraw | 11 ++++++-----
 2 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/R/data.table.R b/R/data.table.R
index 4ece7ec27..eb6333483 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1885,22 +1885,16 @@ as.matrix.data.table <- function(x, rownames, ...) {
   rn <- NULL
   rnc <- NULL
   if (!missing(rownames)) { # Convert rownames to a column index if possible
-    if (is.null(rownames)) {
-      warning("rownames is NULL, ignoring rownames")
-    } else if (length(rownames) == nrow(x)) {
+    if (length(rownames) == nrow(x)) {
       # rownames argument is a vector of row names, no column in x to drop.
       rn <- rownames
       rnc <- NULL 
-    } else if (length(rownames) != 1L) {
+    } else if (!is.null(rownames) && length(rownames) != 1L) { # vector(0) will throw an error, but NULL will pass through
       stop(sprintf("rownames must be a single column in x or a vector of row names of length nrow(x)=%d", nrow(x)))
-    } else if (is.na(rownames)) {
-      warning("rownames is NA, ignoring rownames")
-    } else if (identical(rownames, FALSE)) {
-      warning("rownames is FALSE, ignoring rownames")
-    } else if (!(is.logical(rownames) || is.character(rownames) || is.numeric(rownames))) {
+    } else if (!(is.null(rownames) || is.logical(rownames) || is.character(rownames) || is.numeric(rownames))) {
       # E.g. because rownames is some sort of object that can't be converted to a column index
       stop("rownames must be TRUE, a column index, a column name in x, or a vector of row names")
-    } else { # Handles cases where rownames is a column name, or key(x) from TRUE
+    } else if (!is.null(rownames) && !is.na(rownames) && !identical(rownames, FALSE)) { # Handles cases where rownames is a column name, or key(x) from TRUE
       if (identical(rownames, TRUE)) {
         if (haskey(x)) { 
           rownames <- key(x) 
diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
index 1d083e6fb..308b8c6ba 100644
--- a/inst/tests/tests.Rraw
+++ b/inst/tests/tests.Rraw
@@ -11589,12 +11589,13 @@ test(1899.06, as.matrix(DT, -1), error="rownames is -1 which is outside the colu
 test(1899.07, as.matrix(DT, "Z"), error="Z is not a column of x")
 test(1899.08, as.matrix(DT, c(1,2)), error="rownames must be a single column in x or a vector of row names of length nrow(x)")
 test(1899.09, as.matrix(DT, complex(1)), error="rownames must be TRUE, a column index, a column name in x, or a vector of row names")
-# warnings
-test(1899.10, as.matrix(DT, NA), mat2, warning="rownames is NA, ignoring rownames")
-test(1899.11, as.matrix(DT, NULL), mat2, warning="rownames is NULL, ignoring rownames")
-test(1899.12, as.matrix(DT, FALSE), mat2, warning="rownames is FALSE, ignoring rownames")
+# values that pass through (rownames ignored)
+test(1899.10, as.matrix(DT, NA), mat2)
+test(1899.11, as.matrix(DT, NULL), mat2)
+test(1899.12, as.matrix(DT, FALSE), mat2)
+# Warnings:
 setkey(DT, id, X)
-test(1899.13, as.matrix(DT, TRUE), mat, warning="rownames is TRUE but multiple keys found in key(x), using first column instead")
+test(1899.13, as.matrix(DT, TRUE), mat, warning="rownames is TRUE but multiple keys")
 
 
 ###################################

From a887594f3bd8fd317ef1c31c99d88719fe8d7c37 Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Sun, 1 Apr 2018 15:57:30 +1000
Subject: [PATCH 17/18] Fixed incorrect warning message

---
 R/data.table.R | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/R/data.table.R b/R/data.table.R
index eb6333483..9c2d1c61f 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1899,7 +1899,7 @@ as.matrix.data.table <- function(x, rownames, ...) {
         if (haskey(x)) { 
           rownames <- key(x) 
           if (length(rownames) > 1L) {
-            warning(sprintf("rownames is TRUE but multiple keys [%s] found for x; defaulting to first key column [%s]",
+            warning(sprintf("rownames is TRUE but multiple keys [%s] found for x; defaulting to first column x[,1]",
                             paste(rownames, collapse = ','), rownames[1L]))
             rownames <- 1L
           }

From cde74a29aeeb8399431bec51b7de322fba094d5b Mon Sep 17 00:00:00 2001
From: Scott Ritchie <sritchie73@gmail.com>
Date: Tue, 3 Apr 2018 14:20:56 +1000
Subject: [PATCH 18/18] Removed extraneous newline before tests

---
 inst/tests/tests.Rraw | 1 -
 1 file changed, 1 deletion(-)

diff --git a/inst/tests/tests.Rraw b/inst/tests/tests.Rraw
index 308b8c6ba..ea3f1bffc 100644
--- a/inst/tests/tests.Rraw
+++ b/inst/tests/tests.Rraw
@@ -11572,7 +11572,6 @@ test(1898.1, set2key(DT, a), error="deprecated. Please use setindex() instead.")
 test(1898.2, set2keyv(DT, "a"), error="deprecated. Please use setindexv() instead.")
 test(1898.3, key2(DT), error="deprecated. Please use indices() instead.")
 
-
 # Allow column to be used as rownames when converting to matrix #2702
 DT = data.table(id = letters[1:4], X = 1:4, Y = 5:8)
 mat <- matrix(1:8, ncol = 2, dimnames=list(letters[1:4], c("X", "Y")))