First commit concerning issue-790.

- Added CPFWriter constructor with optional velocity flag
- Added writeEphemerisLine method with optional velocity flag

src/main/java/org/orekit/files/ilrs/CPFWriter.java

@@ -51,16 +51,30 @@ public class CPFWriter implements EphemerisFileWriter {
     /** Time scale for dates. */
     private final TimeScale timescale;
 
+    /** Flag for optional velocity record. */
+    private final boolean velocityFlag;
+
     /**
      * Constructor.
      * @param header container for header data
      * @param timescale time scale for dates
      */
     public CPFWriter(final CPFHeader header, final TimeScale timescale) {
+        this(header, timescale, false);
+    }
+
+    /**
+     * Constructor.
+     * @param header container for header data
+     * @param timescale time scale for dates
+     * @param velocityFlag the flag for the optional velocity record
+     */
+    public CPFWriter(final CPFHeader header, final TimeScale timescale, final boolean velocityFlag) {
         this.header    = header;
         this.timescale = timescale;
-    }
+        this.velocityFlag = velocityFlag;
 
+    }
 
     /** {@inheritDoc} */
     @Override
@@ -93,7 +107,7 @@ public class CPFWriter implements EphemerisFileWriter {
             final Segment segmentWriter = cpfWriter.newSegment(header.getRefFrame());
             // Loop on coordinates
             for (final TimeStampedPVCoordinates coordinates : segment.getCoordinates()) {
-                segmentWriter.writeEphemerisLine(coordinates);
+                segmentWriter.writeEphemerisLine(coordinates, velocityFlag);
             }
         }
 

src/main/java/org/orekit/files/ilrs/StreamingCpfWriter.java

@@ -91,6 +91,9 @@ public class StreamingCpfWriter {
     /** Real 17.3 Format. */
     private static final String F17_3 = "%17.3f";
 
+    /** Real 19.6 Format. */
+    private static final String F19_6 = "%19.6f";
+
     /** Space. */
     private static final String SPACE = " ";
 
@@ -278,7 +281,7 @@ public class StreamingCpfWriter {
         }
 
         /**
-         * Write a single ephemeris line This method does not
+         * Write a single ephemeris line with position record. This method does not
          * write the velocity terms.
          *
          * @param pv the time, position, and velocity to write.
@@ -286,6 +289,18 @@ public class StreamingCpfWriter {
          */
         public void writeEphemerisLine(final TimeStampedPVCoordinates pv)
             throws IOException {
+            writeEphemerisLine(pv, false);
+        }
+
+        /**
+         * Write two ephemeris lines with position and velocity records.
+         *
+         * @param pv the time, position, and velocity to write.
+         * @param velocityFlag flag for the optional velocity record.
+         * @throws IOException if the output stream throws one while writing.
+         */
+        public void writeEphemerisLine(final TimeStampedPVCoordinates pv, final boolean velocityFlag)
+            throws IOException {
 
             // Record type and direction flag
             writeValue(writer, A2, "10",                                    true);
@@ -309,6 +324,23 @@ public class StreamingCpfWriter {
             // New line
             writer.append(NEW_LINE);
 
+            // Write the velocity record
+            if (velocityFlag) {
+
+                // Record type and direction flag
+                writeValue(writer, A2, "20",                                    true);
+                writeValue(writer, I1, DEFAULT_DIRECTION_FLAG,                  true);
+
+                // Velocity
+                final Vector3D velocity = pv.getVelocity();
+                writeValue(writer, F19_6, velocity.getX(), true);
+                writeValue(writer, F19_6, velocity.getY(), true);
+                writeValue(writer, F19_6, velocity.getZ(), false);
+
+                // New line
+                writer.append(NEW_LINE);
+            }
+
         }
 
     }