Today C/C++:.h/.cpp; compiling and linking Fourier Transform (corrected) Nyquist Theorem Audio sampling rates SE-2811 Slide design: Dr. Mark L. Hornick Content: Dr. Hornick Errors: Dr. Yoder 1 SE3910 Week 6, Class 1

Ex: C/C++ (Review) Why do we have both.h and.cpp file extensions for C++? Why not just have.cpp (like.java for Java classes)? Answer these questions: 1. What should you put into a class’s.h file? 2. What should you put into a class’s.cpp file? [Note: On next lab, use.hpp and.cpp instead of.h and.cpp] SE-2811 Dr.Yoder 2

Compiling and Linking Compiling Converting individual.c or.cpp file to object code Linking Combining multiple object (.o) files into an excecutable (usually without extension, or.exe on Windows) SE-2811 Dr.Yoder 3

Ex: C/C++ Circle the link-time errors. Box the compile- time syntax error warning: implicit declaration of function `...' point.m:40: error: ‘mypoint’ undeclared (first use in this function) parse error before `...‘ collect2: ld returned 1 exit status undefined reference to `filterText' /usr/lib/crt1.o(.text+0x18): undefined reference to `main ' SE-2811 Dr.Yoder 4

Network Latency with resmon.exe SE-2811 Dr.Yoder 5

Signals as sums of sine-waves SE Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 6 sSquareWave.html lides/SlideFiles.html

SE Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 7

Sampling Theorem (again Nyquist) f s = 2B (B is bandwidth of signal) SE Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 8

Ex: If this is 1 second, what is the output if we sample 3 times per second? SE Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 9

Units: dB What is a decibel? A tenth of a bel What is a bel? The log 10 of some ratio. X dB = 10 log 10 (Y) Ex: How to compute Y from X? X – in units of dB Y – simple ratio (unitless) e.g. signal power / noise power 10

In-class Activity: Analog to digital bandwidth SE Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 11

Ex: What are two ways we can avoid the stroboscopic effect in a video game simulation of a rotating wheel? SE Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 12

Muddiest Point Wait for the slides, or follow this link to answer both questions at once: SE-2811 Dr.Yoder 13

Muddiest Point Wait for the slides, or follow this link to answer both questions at once: SE-2811 Dr.Yoder 14

SE-2811 Dr. Josiah Yoder 15

SE-2811 Dr. Josiah Yoder 16

References EB: Derek Malloy, Exploring Beaglebone, Wiley, duction_to_gcc/gccintro_95.html theory.co.uk/docs/gccintro/gccintro_95.html c-compile-errors-in-an-basic-example-objc- program duction_to_gcc/gccintro_94.html SE-2811 Slide design: Dr. Mark L. Hornick Content: Dr. Hornick Errors: Dr. Yoder 17