diff --git a/matlab/WriteHDF5.m b/matlab/WriteHDF5.m
new file mode 100644
index 0000000..130e7ca
--- /dev/null
+++ b/matlab/WriteHDF5.m
@@ -0,0 +1,74 @@
+function WriteHDF5(filename,hdf_fielddata,hdf_mesh)
+% function WriteHDF5(filename,hdf_fielddata,hdf_mesh)
+%
+% input:
+%   hdf_fielddata.time
+%   hdf_fielddata.names
+%   hdf_fielddata.values
+%   hdf_mesh.type
+%   hdf_mesh.names
+%   hdf_mesh.lines
+%
+% openEMS matlab interface
+% -----------------------
+% (C) 2010 Sebastian Held <sebastian.held@uni-due.de>
+% See also ReadHDF5FieldData ReadHDF5Mesh
+
+isOctave = exist('OCTAVE_VERSION','builtin') ~= 0;
+if isOctave
+    WriteHDF5_octave(filename,hdf_fielddata,hdf_mesh);
+    return
+end
+
+writemode = 'overwrite';
+if isfield( hdf_fielddata, 'TD' )
+    % this is a time domain data set
+    time = hdf_fielddata.TD.time;
+    for n=1:numel(time)
+        name = ['/FieldData/TD/' int2str(n)];
+        [details.Location, details.Name] = fileparts(name);
+        attribute_details.AttachedTo = name;
+        attribute_details.AttachType = 'dataset';
+        attribute_details.Name = 'time';
+        hdf5write( filename, details, hdf_fielddata.TD.values{n}, ...
+                   attribute_details, time(n), ...
+                   'WriteMode', writemode );
+        writemode = 'append';
+    end
+end
+if isfield( hdf_fielddata, 'FD' )
+    % this is a frequency domain data set
+    freq = hdf_fielddata.FD.freq;
+    for n=1:numel(freq)
+        name = ['/FieldData/FD/f' int2str(n-1) '_real'];
+        [details.Location, details.Name] = fileparts(name);
+        attribute_details.AttachedTo = name;
+        attribute_details.AttachType = 'dataset';
+        attribute_details.Name = 'freq';
+        hdf5write( filename, details, real(hdf_fielddata.FD.values{n}), ...
+                   attribute_details, freq(n), ...
+                   'WriteMode', writemode );
+        name = ['/FieldData/FD/f' int2str(n-1) '_imag'];
+        [details.Location, details.Name] = fileparts(name);
+        attribute_details.AttachedTo = name;
+        attribute_details.AttachType = 'dataset';
+        attribute_details.Name = 'freq';
+        hdf5write( filename, details, imag(hdf_fielddata.FD.values{n}), ...
+                   attribute_details, freq(n), ...
+                   'WriteMode', 'append' );
+        writemode = 'append';
+    end
+end
+
+names = hdf_mesh.names; % names is a cell array
+for n=1:numel(names)
+    [details.Location, details.Name, ext] = fileparts(names{n});
+    details.Name = [details.Name ext];
+    hdf5write( filename, details, hdf_mesh.lines{n}, ...
+               'WriteMode', 'append' );
+end
+
+
+
+function WriteHDF5_octave(filename,hdf_fielddata,hdf_mesh)
+error 'not yet implemented'