Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help memtoc”.

  MEMTOC return the memory that was used
    MEMTIC and MEMTOC functions work together to measure memory usage.
    MEMTIC, by itself, saves the current memory footprint that MEMTOC
    uses later to measure the memory that was used between the two.
  Use as
  to print the estimated memory use on screen, or
    M = MEMTOC
  to return the estimated memory (in bytes) in variable M, or
    C = MEMTIC
    M = MEMTOC(C)
  to specifically estimate the memory use between a well-defined tic/toc pair.
  Note that MATLAB uses internal memory allocation, garbage collection, shallow
  copies of variables, and virtual memory. Due to the advanced handling of
  memory for its variables, it is not easy and in certain cases not possible to
  make a reliable and reproducible estimate based on the memory information
  provided by the operating system.
  Example: measure the memory increase due to allocating a lot of memory.
  Doing a "clear x" following the allocation and priot to MEMTOC does not
  affect the memory that is reported.
    n = 125; x = cell(1,n);
    for i=1:n
      x{i} = randn(1000,1000); % 8kB per item
    whos x
  See also TIC, TOC