diff --git a/utils/sample-element.cpp b/utils/sample-element.cpp
index 9797bd2..57a8714 100644
--- a/utils/sample-element.cpp
+++ b/utils/sample-element.cpp
@@ -1,39 +1,103 @@
-#include <iostream>
-#include <string>
+/*
+ * sample-element.cpp, part of LatAnalyze 3
+ *
+ * Copyright (C) 2013 - 2016 Antonin Portelli, Matt Spraggs
+ *
+ * LatAnalyze 3 is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LatAnalyze 3 is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with LatAnalyze 3.  If not, see <http://www.gnu.org/licenses/>.
+ */
 
+#include <LatCore/OptParser.hpp>
 #include <LatAnalyze/Io.hpp>
 #include <LatAnalyze/MatSample.hpp>
 
+using namespace std;
+using namespace Latan;
 
 int main(int argc, char* argv[])
 {
-    using namespace std;
-    using namespace Latan;
-
-    if (argc != 4 and argc != 5) {
-        cout << "Usage: " << argv[0] << " <input filename> <row> <column> ";
-        cout << "[output filename]" << endl;
-        return -1;
+    // argument parsing ////////////////////////////////////////////////////////
+    OptParser opt;
+    bool      parsed;
+    string    inFilename, outFilename;
+    Index     r, c, nr, nc;
+    
+    opt.addOption("r", "row",    OptParser::OptType::value  , false,
+                  "row");
+    opt.addOption("c", "col",    OptParser::OptType::value  , false,
+                  "column");
+    opt.addOption("" , "nrow",   OptParser::OptType::value  , true,
+                  "number of rows (default: 1)", "1");
+    opt.addOption("" , "ncol",   OptParser::OptType::value  , true,
+                  "number of columns (default: 1)", "1");
+    opt.addOption("o", "output", OptParser::OptType::value  , true,
+                  "output file name (default: result not saved)", "");
+    opt.addOption("" , "help"  , OptParser::OptType::trigger, true,
+                  "show this help message and exit");
+    parsed = opt.parse(argc, argv);
+    if (!parsed or (opt.getArgs().size() != 1) or opt.gotOption("help"))
+    {
+        cerr << "usage: " << argv[0];
+        cerr << " <options> <input file>" << endl;
+        cerr << endl << "Possible options:" << endl << opt << endl;
+        
+        return EXIT_FAILURE;
     }
-
-    string inFileName = argv[1];
-    auto row = strTo<Index>(argv[2]);
-    auto col = strTo<Index>(argv[3]);
-    string outFileName = (argc == 5) ? argv[4] : "";
-
-    auto inputData = Io::load<DMatSample>(inFileName);
-    cout << scientific;
-    cout << "central value:\n" << inputData[central](row, col) << endl;
-    cout << "standard deviation:\n";
-    cout << inputData.variance().cwiseSqrt()(row, col) << endl;
-
-    if (not outFileName.empty())
+    inFilename  = opt.getArgs()[0];
+    outFilename = opt.optionValue("o");
+    r           = opt.optionValue<Index>("r");
+    c           = opt.optionValue<Index>("c");
+    nr          = opt.optionValue<Index>("nrow");
+    nc          = opt.optionValue<Index>("ncol");
+    
+    // Data extraction /////////////////////////////////////////////////////////
+    auto inputData = Io::load<DMatSample>(inFilename);
+    
+    if ((nr == 1) and (nc == 1))
     {
         DSample outputData(inputData.size());
-        FOR_STAT_ARRAY(inputData, s) {
-            outputData[s] = inputData[s](row, col);
+        
+        FOR_STAT_ARRAY(inputData, s)
+        {
+            outputData[s] = inputData[s](r, c);
+        }
+        
+        cout << scientific;
+        cout << "central value:\n" << outputData[central] << endl;
+        cout << "standard deviation:\n";
+        cout << sqrt(outputData.variance()) << endl;
+        if (not outFilename.empty())
+        {
+            Io::save(outputData, outFilename);
         }
-
-        Io::save(outputData, outFileName);
     }
+    else
+    {
+        DMatSample outputData(inputData.size(), nr, nc);
+        
+        FOR_STAT_ARRAY(inputData, s)
+        {
+            outputData[s] = inputData[s].block(r, c, nr, nc);
+        }
+        cout << scientific;
+        cout << "central value:\n" << outputData[central] << endl;
+        cout << "standard deviation:\n";
+        cout << outputData.variance().cwiseSqrt() << endl;
+        if (not outFilename.empty())
+        {
+            Io::save(outputData, outFilename);
+        }
+    }
+
+    return EXIT_SUCCESS;
 }