MATLAB Programming Fundamentals - MathWorks

Performance

28

Measure Performance of Your Program ............. 28-2

Overview of Performance Timing Functions......... 28-2

Time Functions............................... 28-2

Time Portions of Code.......................... 28-2

The cputime Function vs. tic/toc and timeit.......... 28-3

Tips for Measuring Performance .................. 28-3

Profile to Improve Performance.................... 28-5

What Is Profiling?............................. 28-5

Profiling Process and Guidelines .................. 28-5

Using the Profiler ............................. 28-6

Profile Summary Report........................ 28-8

Profile Detail Report........................... 28-9

Use Profiler to Determine Code Coverage........... 28-12

Techniques to Improve Performance............... 28-14

Environment............................... 28-14

Code Structure .............................. 28-14

Programming Practices for Performance........... 28-14

Tips on Specific MATLAB Functions.............. 28-15

Preallocation .................................. 28-17

Preallocating a Nondouble Matrix............... 28-17

Vectorization.................................. 28-19

Using Vectorization .......................... 28-19

Array Operations............................ 28-20

Logical Array Operations...................... 28-22

Matrix Operations........................... 28-23

Ordering, Setting, and Counting Operations........ 28-24

Functions Commonly Used in Vectorization........ 28-26

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