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diff --git a/src/stlplus/persistence/persistent_float.cpp b/src/stlplus/persistence/persistent_float.cpp
new file mode 100644
index 0000000..59a6678
--- /dev/null
+++ b/src/stlplus/persistence/persistent_float.cpp
@@ -0,0 +1,86 @@
+////////////////////////////////////////////////////////////////////////////////
+
+//   Author:    Andy Rushton
+//   Copyright: (c) Southampton University 1999-2004
+//              (c) Andy Rushton           2004-2009
+//   License:   BSD License, see ../docs/license.html
+
+////////////////////////////////////////////////////////////////////////////////
+#include "persistent_float.hpp"
+
+////////////////////////////////////////////////////////////////////////////////
+// Macro for mapping either endian data onto little-endian addressing to make
+// my life easier in writing this code! I think better in little-endian mode
+// so the macro does nothing in that mode but maps little-endian onto
+// big-endian addressing in big-endian mode
+// TODO - make this compile-time configurable
+
+#define INDEX(index) ((context.little_endian()) ? (index) : ((bytes) - (index) - 1))
+
+/////////////////////////////////////////////////////////////////////
+// floating point types
+// format: {size}{byte}*size
+// ordering is msB first
+
+// this uses a similar mechanism to integer dumps. However, it is not clear how
+// the big-endian and little-endian argument applies to multi-word data so
+// this may need reworking by splitting into words and then bytes.
+
+namespace stlplus
+{
+
+  static void dump_float(stlplus::dump_context& context, unsigned bytes, unsigned char* data)
+    throw(stlplus::persistent_dump_failed)
+  {
+    unsigned i = bytes;
+    // put the size
+    context.put((unsigned char)i);
+    // and put the bytes
+    while(i--)
+      context.put(data[INDEX(i)]);
+  }
+
+  static void restore_float(stlplus::restore_context& context, unsigned bytes, unsigned char* data)
+    throw(stlplus::persistent_restore_failed)
+  {
+    // get the dumped size from the file
+    unsigned dumped_bytes = (unsigned)context.get();
+    // get the bytes from the file
+    unsigned i = dumped_bytes;
+    while(i--)
+    {
+      int ch = context.get();
+      if (i < bytes)
+        data[INDEX(i)] = (unsigned char)ch;
+    }
+    // however, if the dumped size was different I don't know how to map the formats, so give an error
+    if (dumped_bytes != bytes)
+      throw stlplus::persistent_restore_failed(std::string("size mismatch"));
+  }
+
+} // end namespace stlplus
+
+  ////////////////////////////////////////////////////////////////////////////////
+  // exported functions which simply call the low-level byte-dump and byte-restore routines above
+
+void stlplus::dump_float(stlplus::dump_context& context, const float& data) throw(stlplus::persistent_dump_failed)
+{
+  stlplus::dump_float(context, sizeof(float), (unsigned char*)&data);
+}
+
+void stlplus::restore_float(restore_context& context, float& data) throw(stlplus::persistent_restore_failed)
+{
+  stlplus::restore_float(context, sizeof(float), (unsigned char*)&data);
+}
+
+void stlplus::dump_double(stlplus::dump_context& context, const double& data) throw(stlplus::persistent_dump_failed)
+{
+  stlplus::dump_float(context, sizeof(double), (unsigned char*)&data);
+}
+
+void stlplus::restore_double(restore_context& context, double& data) throw(stlplus::persistent_restore_failed)
+{
+  stlplus::restore_float(context, sizeof(double), (unsigned char*)&data);
+}
+
+////////////////////////////////////////////////////////////////////////////////