[c++/m] Add Tag compare function

Author: mpsonntag

nix_mx.cc

@@ -311,6 +311,7 @@ void mexFunction(int            nlhs,
         methods->add("Tag::openReferenceIdx", nixtag::openReferenceIdx);
         methods->add("Tag::openFeatureIdx", nixtag::openFeatureIdx);
         methods->add("Tag::openSourceIdx", nixtag::openSourceIdx);
+        methods->add("Tag::compare", nixtag::compare);
 
         classdef<nix::MultiTag>("MultiTag", methods)
             .desc(&nixmultitag::describe)

src/nixtag.cc

@@ -96,4 +96,10 @@ namespace nixtag {
         output.set(0, currObj.getSource(idx));
     }
 
+    void compare(const extractor &input, infusor &output) {
+        nix::Tag currObj = input.entity<nix::Tag>(1);
+        nix::Tag other = input.entity<nix::Tag>(2);
+        output.set(0, currObj.compare(other));
+    }
+
 } // namespace nixtag

src/nixtag.h

@@ -35,6 +35,8 @@ namespace nixtag {
 
     void openSourceIdx(const extractor &input, infusor &output);
 
+    void compare(const extractor &input, infusor &output);
+
 } // namespace nixtag
 
 #endif

tests/TestTag.m

@@ -39,6 +39,7 @@
     funcs{end+1} = @test_attrs;
     funcs{end+1} = @test_has_feature;
     funcs{end+1} = @test_has_reference;
+    funcs{end+1} = @test_compare;
 end
 
 %% Test: Add sources by entity and id
@@ -636,3 +637,18 @@
     f = nix.File(fullfile(pwd, 'tests', fileName), nix.FileMode.ReadOnly);
     assert(f.blocks{1}.tags{1}.has_reference(daName));
 end
+
+function [] = test_compare( varargin )
+%% Test: Compare Tag entities
+    f = nix.File(fullfile(pwd, 'tests', 'testRW.h5'), nix.FileMode.Overwrite);
+    b1 = f.create_block('testBlock1', 'nixBlock');
+    b2 = f.create_block('testBlock2', 'nixBlock');
+    t1 = b1.create_tag('testTag1', 'nixTag', [1 2 3]);
+    t2 = b1.create_tag('testTag2', 'nixTag', [1 2 3]);
+    t3 = b2.create_tag('testTag1', 'nixTag', [1 2 3]);
+
+    assert(t1.compare(t2) < 0);
+    assert(t1.compare(t1) == 0);
+    assert(t2.compare(t1) > 0);
+    assert(t1.compare(t3) ~= 0);
+end