Added the possibility to extract a dynDate object from a dynDates object.

*Example* If a dynDates object is built as follows

d1 = dynDate('1966Q4');
d2 = dynDate('2013Q1');
dd = d1:d2;

then dd(2) is a dynDate object (should be equal to dynDate('1967Q1')).

matlab/@dynDates/dynDates.m

@@ -168,21 +168,21 @@ end
 %@eof:3
 
 %@test:4
-%$ % Define some dates
-%$ B1 = '1945Q1';
-%$ B2 = '1950Q3';
-%$ B3 = '1950M10';
-%$ B4 = '1953Q1';
+%$ % Define a dynDates object
+%$ B = dynDate('1950Q1'):dynDate('1960Q3');
 %$
 %$
 %$ % Call the tested routine.
-%$ try
-%$     d = dynDates(B1,B2,B3,B4);
-%$     t(1) = 0;
-%$     T = 0;
-%$ catch
-%$     % Expected issue...
+%$ d = B(2);
+%$ if isa(d,'dynDate')
 %$     t(1) = 1;
-%$     T = 1;
+%$ else
+%$     t(1) = 0;
 %$ end
+%$
+%$ if t(1)
+%$     t(2) = dyn_assert(d.freq,B.freq);
+%$     t(3) = dyn_assert(d.time,[1950 2]);
+%$ end
+%$ T = all(t);
 %@eof:4
\ No newline at end of file

matlab/@dynDates/subsref.m

@@ -69,10 +69,11 @@ if isequal(S(1).type,'.')
         error('dynDates::subsref: Unknown public method or member!')
     end
 elseif isequal(S.type,'()')                                                    % Extract a sub-sample.
-    if length(S.subs)==1
-        S.subs = [S.subs, ':'];
+    if isscalar(S.subs) && isint(S.subs{1}) && S.subs{1}>0 && S.subs{1}<A.ndat
+        B = dynDate(A.time(S.subs{1},:),A.freq);
+    else
+        B = builtin('subsref', A.time, S);
     end
-    B = builtin('subsref', A.time, S);
 else
     error('dynDates::subsref: Something is wrong in your syntax!')
 end