* MappedTensors can now be specified as read-only, to protect important raw data. Attempting to write to a read-only tensor raises an error.

* Added several overloaded tests such as `ischar`, `islogical`, `isscalar`, etc.
* Fixed minor indentation issue in `mapped_tensor_shim`

Author: DylanMuir

MappedTensor.m

@@ -149,6 +149,7 @@
    properties (SetAccess = private, GetAccess = private)
       strRealFilename;        % Binary data file on disk (real part of tensor)
       strCmplxFilename;       % Binary data file on disk (complex part of tensor)
+      bReadOnly = false;      % Should the data be protected from writing?
       hRealContent;           % File handle for data (real part)
       hCmplxContent;          % File handle for data (complex part)
       bTemporary;             % A flag which records whether a temporary file was created by MappedTensor
@@ -198,6 +199,12 @@
                      vbKeepArg(nArg:nArg+1) = false;
                      nArg = nArg + 1;
 
+                  case {'readonly'}
+                     % - Read-only or read/write status was specified
+                     mtVar.bReadOnly = logical(varargin{nArg+1});
+                     vbKeepArg(nArg:nArg+1) = false;
+                     nArg = nArg + 1;
+                     
                   otherwise
                      % - No other properties are supported
                      error('MappedTensor:InvalidProperty', ...
@@ -447,6 +454,11 @@ function delete(mtVar)
 
       % subsasgn - METHOD Overloaded subsasgn
       function [mtVar] = subsasgn(mtVar, subs, tfData)
+         % - Test read-only status if tensor
+         if (mtVar.bReadOnly)
+            error('MappedTensor:ReadProtect', '*** MappedTensor: Attempted write to a read-only tensor.');
+         end
+         
          % - Test real/complex nature of input and current tensor
          if (~isreal(tfData))
             % - The input data is complex
@@ -578,6 +590,36 @@ function delete(mtVar)
          bIsReal = ~mtVar.bIsComplex;
       end
 
+      % islogical - METHOD Overloaded islogical function
+      function [bIsLogical] = islogical(mtVar)
+         bIsLogical = isequal(mtVar.strClass, 'logical');
+      end
+      
+      % isnumeric - METHOD Overloaded isnumeric function
+      function [bIsNumeric] = isnumeric(mtVar)
+         bIsNumeric = ~islogical(mtVar);
+      end
+      
+      % isscalar - METHOD Overloaded isscalar function
+      function [bIsScalar] = isscalar(mtVar)
+         bIsScalar = numel(mtVar) == 1;
+      end
+      
+      % ismatrix - METHOD Overloaded ismatrix function
+      function [bIsMatrix] = ismatrix(mtVar)
+         bIsMatrix = ~isscalar(mtVar);
+      end
+      
+      % ischar - METHOD Overloaded ischar function
+      function [bIsChar] = ischar(mtVar)
+         bIsChar = isequal(mtVar.strClass, 'char');
+      end
+      
+      % isnan - METHOD Overloaded isnan function
+      function [bIsNan] = isnan(mtVar) %#ok<MANU>
+         bIsNan = false;
+      end
+      
       %% Overloaded methods (uminus, uplus, times, mtimes, ldivide, rdivide, mldivide, mrdivide)
 
       % uminus - METHOD Overloaded uminus operator (-mtVar)

private/mapped_tensor_shim.c

@@ -510,7 +510,7 @@ void CmdReadChunks(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
 
       } else {
 
-			dprintf("mts/crc: Single-element skip-read: read [%ld] bytes per element, skip [%ld] bytes.\n", nDataElemSize, nDataElemSize * (uChunkSkip-1));
+			   dprintf("mts/crc: Single-element skip-read: read [%ld] bytes per element, skip [%ld] bytes.\n", nDataElemSize, nDataElemSize * (uChunkSkip-1));
 
          /* - Read an element, then skip elements */
          for (uElementIndex = 0; uElementIndex < uChunkSize; uElementIndex++) {