[c++/m] Add DataArray dataExtent handling

- Changes matlab dynamic attribute "shape" to the
original designation "dataExtent".
- Adds the setDataExtent method on the c++ and
the matlab side and introduces a corresponding test.

Author: mpsonntag

+nix/DataArray.m

@@ -29,7 +29,7 @@
             nix.Dynamic.add_dyn_attr(obj, 'unit', 'rw');
             nix.Dynamic.add_dyn_attr(obj, 'expansionOrigin', 'rw');
             nix.Dynamic.add_dyn_attr(obj, 'polynomCoefficients', 'rw');
-            nix.Dynamic.add_dyn_attr(obj, 'shape', 'rw');
+            nix.Dynamic.add_dyn_attr(obj, 'dataExtent', 'rw');
         end;
 
         % -----------------
@@ -129,6 +129,20 @@ function write_all(obj, data)
         function s = datatype(obj)
             s = nix_mx('DataArray::dataType', obj.nix_handle);
         end
-
+        
+        % set data extent enabels to increase the original size 
+        % of a data array within the same dimensions.
+        % e.g. increase the size of a 2D array [5 10] to another
+        % 2D array [5 11]. Changing the dimensions is not possible
+        % e.g. changing from a 2D array to a 3D array.
+        % Furthermore if the extent shrinks the size of an array
+        % or remodels the size of an array to a completely different
+        % shape, existing data that does not fit into the new shape
+        % will be lost!
+        function [] = set_data_extent(obj, extent)
+            nix_mx('DataArray::setDataExtent', obj.nix_handle, extent);
+            % update changed dataExtent in obj.info
+            obj.info = nix_mx(strcat(obj.alias, '::describe'), obj.nix_handle);
+        end
     end;
 end

nix_mx.cc

@@ -234,6 +234,7 @@ void mexFunction(int            nlhs,
         methods->add("DataArray::dimensionCount", nixdataarray::dimensionCount);
         methods->add("DataArray::setPolynomCoefficients", nixdataarray::polynomCoefficients);
         methods->add("DataArray::dataType", nixdataarray::dataType);
+        methods->add("DataArray::setDataExtent", nixdataarray::setDataExtent);
 
         classdef<nix::Source>("Source", methods)
             .desc(&nixsource::describe)

src/nixdataarray.cc

@@ -21,7 +21,7 @@ namespace nixdataarray {
 
     mxArray *describe(const nix::DataArray &da) {
         struct_builder sb({ 1 }, { "id", "type", "name", "definition", "label",
-            "shape", "unit", "expansionOrigin", "polynomCoefficients" });
+            "dataExtent", "unit", "expansionOrigin", "polynomCoefficients" });
 
         sb.set(da.id());
         sb.set(da.type());
@@ -130,4 +130,10 @@ namespace nixdataarray {
         output.set(0, string_nix2mex(da.dataType()));
     }
 
+    void setDataExtent(const extractor &input, infusor &output) {
+        nix::DataArray da = input.entity<nix::DataArray>(1);
+        nix::NDSize size = input.ndsize(2);
+        da.dataExtent(size);
+    }
+
 } // namespace nixdataarray

src/nixdataarray.h

@@ -39,6 +39,8 @@ namespace nixdataarray {
 
     void dataType(const extractor &input, infusor &output);
 
+    void setDataExtent(const extractor &input, infusor &output);
+
 } // namespace nixdataarray
 
 #endif

tests/TestDataArray.m

@@ -29,6 +29,7 @@
     funcs{end+1} = @test_dimensions;
     funcs{end+1} = @test_dimension_count;
     funcs{end+1} = @test_datatype;
+    funcs{end+1} = @test_set_data_extent;
 end
 
 function [] = test_attrs( varargin )
@@ -484,11 +485,11 @@
 
     daAliasWa = f.blocks{1}.create_data_array_from_data('aliasDimWATest2', ...
         'nix.DataArray', [1; 2; 3]);
-    assert(isequal(daAliasWa.shape, [3 1]));
+    assert(isequal(daAliasWa.dataExtent, [3 1]));
 
     daAliasWa = f.blocks{1}.create_data_array_from_data('aliasDimWATest3', ...
         'nix.DataArray', [1 2 3; 2 4 5; 3 6 7]);
-    assert(isequal(daAliasWa.shape, [3 3]));
+    assert(isequal(daAliasWa.dataExtent, [3 3]));
 end
 
 %% Test: Dimension count
@@ -530,3 +531,15 @@
     da.write_all(logical([1 0 1 1 1]));
     assert(strcmp(da.datatype, 'logical'));
 end
+
+%% Test: Set extent
+function [] = test_set_data_extent( varargin )
+    fileName = fullfile(pwd, 'tests', 'testRW.h5');
+    f = nix.File(fileName, nix.FileMode.Overwrite);
+    b = f.create_block('testBlock', 'nixblock');
+
+    da = b.create_data_array_from_data('testDataArray1', 'nix.DataArray', [1 2 3; 4 5 6]);
+    extent = [4 6];
+    da.set_data_extent(extent);
+    assert(da.dataExtent(1) == extent(1) && size(da.read_all, 2) == extent(2));
+end