Index: /trunk/FACT++/src/RowChecker.cc
===================================================================
--- /trunk/FACT++/src/RowChecker.cc	(revision 12730)
+++ /trunk/FACT++/src/RowChecker.cc	(revision 12730)
@@ -0,0 +1,114 @@
+/*
+ * RowChecker.cc
+ *
+ *  Created on: Dec 20, 2011
+ *      Author: lyard
+ */
+
+#include <fstream>
+#include <cstdlib>
+#include <iostream>
+#include <cstring>
+#include <sstream>
+
+using namespace std;
+
+
+//usage RowChecker <name of file> <size of header> <size of line> <mjdref> <givenLines>
+int main(int argc, char** argv)
+{
+
+    if (argc < 6)
+        return 0;
+
+    fstream file(argv[1]);
+
+    int headLen = atoi(argv[2]);
+    int lineWidth = atoi(argv[3]);
+    double mjdRef = atof(argv[4]);
+    int numLines = atoi(argv[5]);
+
+    int totalBytes = headLen;
+    file.seekp(headLen);
+
+    char* buf = new char[lineWidth];
+
+    double currentTime = 0;
+    char timeBuf[16];
+    int realNumRows = 0;
+
+    while (file.read(buf, lineWidth))
+    {
+        timeBuf[0] = buf[7];
+        timeBuf[1] = buf[6];
+        timeBuf[2] = buf[5];
+        timeBuf[3] = buf[4];
+        timeBuf[4] = buf[3];
+        timeBuf[5] = buf[2];
+        timeBuf[6] = buf[1];
+        timeBuf[7] = buf[0];
+        currentTime = reinterpret_cast<double*>(timeBuf)[0];
+
+        if (realNumRows >= numLines)
+        {
+            if (currentTime + mjdRef > 60000 || currentTime + mjdRef < 10000)
+                break;
+            if (currentTime + mjdRef > 20000 && currentTime + mjdRef < 50000)
+                break;
+        }
+//fix the time column if required.
+        if (currentTime > 50000 && currentTime < 60000)
+        {
+            currentTime -= 40587;
+            reinterpret_cast<double*>(timeBuf)[0] = currentTime;
+            file.seekp(totalBytes);
+            file.put(timeBuf[7]);
+            file.put(timeBuf[6]);
+            file.put(timeBuf[5]);
+            file.put(timeBuf[4]);
+            file.put(timeBuf[3]);
+            file.put(timeBuf[2]);
+            file.put(timeBuf[1]);
+            file.put(timeBuf[0]);
+            file.seekp(totalBytes + lineWidth);
+        }
+
+        realNumRows++;
+        totalBytes += lineWidth;
+    }
+    //now update the number of lines of the file
+    file.close();
+    file.open(argv[1]);
+    file.seekp(2880);
+    delete[] buf;
+    buf = new char[81];
+    buf[80] = 0;
+    bool changeDone = false;
+    int seeked = 2880;
+    if (realNumRows == numLines)
+        changeDone = true;
+
+    while (file.good() && !changeDone)
+    {
+        file.read(buf, 80);
+        string str(buf);
+
+        if (str.substr(0,9) == "NAXIS2  =")
+        {
+            ostringstream ss;
+            ss << realNumRows;
+            file.seekp(seeked + 30 - ss.str().size());
+            for (int i=0;i<ss.str().size();i++)
+                file.put(ss.str()[i]);
+            changeDone = true;
+            break;
+        }
+        seeked += 80;
+    }
+    if (!changeDone)
+        cout << -1;
+    else
+        cout << realNumRows;
+    file.close();
+    return realNumRows;
+}