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+ | ===== MEMTOC ===== | ||
+ | |||
+ | Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help memtoc". | ||
+ | |||
+ | <html><pre> | ||
+ | <a href=/reference/memtoc><font color=green>MEMTOC</font></a> return the memory that was used | ||
+ | |||
+ | <a href=/reference/memtic><font color=green>MEMTIC</font></a> and <a href=/reference/memtoc><font color=green>MEMTOC</font></a> functions work together to measure memory usage. | ||
+ | <a href=/reference/memtic><font color=green>MEMTIC</font></a>, by itself, saves the current memory footprint that <a href=/reference/memtoc><font color=green>MEMTOC</font></a> | ||
+ | uses later to measure the memory that was used between the two. | ||
+ | |||
+ | Use as | ||
+ | <a href=/reference/memtic><font color=green>MEMTIC</font></a> | ||
+ | <a href=/reference/memtoc><font color=green>MEMTOC</font></a> | ||
+ | to print the estimated memory use on screen, or | ||
+ | <a href=/reference/memtic><font color=green>MEMTIC</font></a> | ||
+ | M = <a href=/reference/memtoc><font color=green>MEMTOC</font></a> | ||
+ | to return the estimated memory (in bytes) in variable M, or | ||
+ | C = <a href=/reference/memtic><font color=green>MEMTIC</font></a> | ||
+ | M = <a href=/reference/memtoc><font color=green>MEMTOC</font></a>(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 <a href=/reference/memtoc><font color=green>MEMTOC</font></a> does not | ||
+ | affect the memory that is reported. | ||
+ | |||
+ | memtic | ||
+ | n = 125; x = cell(1,n); | ||
+ | for i=1:n | ||
+ | x{i} = randn(1000,1000); % 8kB per item | ||
+ | disp(i); | ||
+ | end | ||
+ | whos x | ||
+ | memtoc | ||
+ | |||
+ | See also TIC, TOC | ||
+ | </pre></html> | ||