code: public static Matrix readMatrix(File matrix, Format format)
               throws IOException {
           switch (format) {
               // Assume all sparse formats will fit in memory.
               case SVDLIBC_SPARSE_TEXT:
               case SVDLIBC_SPARSE_BINARY:
               case MATLAB_SPARSE:
               case CLUTO_SPARSE:
                   return readMatrix(matrix, format, 
                                     Type.SPARSE_IN_MEMORY, false);
               // Assume all dense formats will fit in memory.
               case SVDLIBC_DENSE_TEXT:
               case SVDLIBC_DENSE_BINARY:
               case DENSE_TEXT:
               case CLUTO_DENSE:
                   return readMatrix(matrix, format,
                                     Type.DENSE_IN_MEMORY, false);
               default:
                   throw new Error(
                           "Reading matrices of " + format + " format is not "+
                           "currently supported. Email " +
                           "s-space-research-dev@googlegroups.com to request " +
                           "its inclusion and it will be quickly added");
           }
       }
docs: Converts the contents of a matrix file as a {@link Matrix} object, using
  the provided format as a hint for what kind to create.  The
  type of {@code Matrix} object created will assuming that the entire
  matrix can fit in memory based on the format of the file speicfied
  Note that the returned {@link Matrix} instance is not backed by the data
  on file; changes to the {@code Matrix} will <i>not</i> be reflected in
  the original file's data.
  
  @param matrix a file contain matrix data
  @param format the format of the file
  
  @return the {@code Matrix} instance that contains the data in the
  provided file