From: rich <rich>
Date: Wed, 18 Oct 2006 14:56:12 +0000 (+0000)
Subject: Csv.concat - arranges CSV subfiles in columns.
X-Git-Url: http://git.annexia.org/?a=commitdiff_plain;h=af6726a634255b49167e1aa90d92103c3769dc90;p=ocaml-csv.git

Csv.concat - arranges CSV subfiles in columns.
---

diff --git a/csv.ml b/csv.ml
index 6ca424b..b76f4b3 100644
--- a/csv.ml
+++ b/csv.ml
@@ -1,6 +1,6 @@
 (* csv.ml - comma separated values parser
  *
- * $Id: csv.ml,v 1.11 2006-07-19 09:41:58 rich Exp $
+ * $Id: csv.ml,v 1.12 2006-10-18 14:56:12 rich Exp $
  *)
 
 (* The format of CSV files:
@@ -299,6 +299,27 @@ let rec compare (csv1 : t) csv2 =
       let c = compare_row [] y in
       if c <> 0 then c else compare [] ys
 
+(* Concatenate - arrange left to right. *)
+let rec concat = function
+  | [] -> []
+  | [csv] -> csv
+  | left_csv :: csvs ->
+      (* Concatenate the remaining CSV files. *)
+      let right_csv = concat csvs in
+
+      (* Set the height of the left and right CSVs to the same. *)
+      let nr_rows = max (lines left_csv) (lines right_csv) in
+      let left_csv = set_rows nr_rows left_csv in
+      let right_csv = set_rows nr_rows right_csv in
+
+      (* Square off the left CSV. *)
+      let left_csv = square left_csv in
+
+      (* Prepend the right CSV rows with the left CSV rows. *)
+      List.map (
+	fun (left_row, right_row) -> List.append left_row right_row
+      ) (List.combine left_csv right_csv)
+
 let to_array csv =
   Array.of_list (List.map Array.of_list csv)
 
diff --git a/csv.mli b/csv.mli
index ef061e6..983fce1 100644
--- a/csv.mli
+++ b/csv.mli
@@ -1,6 +1,6 @@
 (** csv.mli - comma separated values parser
   *
-  * $Id: csv.mli,v 1.8 2006-02-23 15:24:25 rich Exp $
+  * $Id: csv.mli,v 1.9 2006-10-18 14:56:12 rich Exp $
   *)
 
 type t = string list list
@@ -112,6 +112,15 @@ val compare : t -> t -> int
   * look the same if opened in a spreadsheet program.
   *)
 
+val concat : t list -> t
+(** Concatenate CSV files so that they appear side by side, arranged
+  * left to right across the page.  Each CSV file (except the final
+  * one) is first squared.
+  *
+  * (To concatenate CSV files so that they appear from top to bottom,
+  * just use {!List.concat}).
+  *)
+
 val to_array : t -> string array array
 val of_array : string array array -> t
 (** Convenience functions to convert to and from a matrix representation.