4/23/2015Engineering Problem Solving with C++ second edition, J. ingber 1 Engineering Problem Solving with C++, Etter/Ingber Chapter 1

04/18/23 Engineering Problem Solving with C++ second edition, J. ingber

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Engineering Problem Solving with C++, Etter/Ingber

Chapter 1

Introduction to Computing and Engineering Problem Solving

Historical Perspective Recent Engineering Achievements Computing Systems Data Representation and Storage An Engineering Problem Solving Methodology


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HISTORICAL PERSPECTIVE

Charles Babbage

Analytical Engine

Augusta Ada Byron

Digital Computers


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Charles Babbage, Esq. 1792-1871

English mathematician. Designed the Analytical Engine in the early

1800s. Published “Of the Analytical Engine” in

1864.04/18/23 Engineering Problem Solving with

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Analytical Engine

Designed to process base ten numbers. Consisted of four parts:

– Storage unit– Processing unit– Input device– Output device


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Analytical Engine

Luigi F. Menabrea, French engineer and mathematician, described Babbage’s vision of a machine capable of solving any problem using: – Inputs– Outputs– Programs written on punch cards


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Augusta Ada Byron, 1815-1852

Wrote the English translation of Menabrea’s Sketch of the Analytical Engine.

Envisioned the multidisciplinary potential of the Analytical Engine.

Wrote detailed instructions for performing numerical computations using the Analytical Engine.


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Digital Computers ABC (Atanasoff Berry Computer)

• Developed at Iowa State University between 1939 and 1942 by John Atanasoff and Clifford Berry.

• Weighed 700 pounds.

• Executed one instruction every 15 seconds.


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Digital Computers ENIAC(Electronic Numerical Integrator

And Calculator)• Developed by research team lead by John Mauchly

and J. Presper Eckert during the early 1940s.

• Weighed 30 tons.

• Executed hundreds of instructions every second.


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Digital Computers

Intel Pentium 4 Processor.• Weighs < 16 ounces.

• Executes trillions of instructions per second.


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RECENT ENGINEERING ACHIEVEMENTS


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Recent Engineering Achievements

Digital computers facilitate multidisciplinary engineering achievements that:– Improve our lives

– Expanded the possibilities for our future.

Changing engineering environment requires engineers with:– Communication skills

– Skills for working in interdisciplinary teams

– An awareness of ethic issues and environmental concerns.


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COMPUTING SYSTEMS

Computer Hardware

Computer Software


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Computing Systems

A computing system is a complete working system that includes:– Hardware– Software


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Hardware

Hardware refers to the physical parts off the computing system that have mass (ie they can actually be touched):– Computer– Display– Mouse– Printer– …


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Computer Hardware

Jon von Neumann computing model– Input device– Output device– Memory Unit– CPU(Central Processing Unit) consisting of:

• Control Unit

• ALU(Arithmetic Logic Unit)


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Von Neumann computing model


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Software Computer software refers to programs that

reside and execute electronically on the hardware.– Compilers

– Translate source code

– Operating systems– Provide the HCI (Human Computer Interface)

– Application programs– Provide problem solutions


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Hierarchy of Computer Languages

Natural Language Processing Cobol Pascal Java C++ Assembler Machine Language04/18/23 Engineering Problem Solving with

C++ second edition, J. ingber19

Executing a C++


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Key Terms Source Program

– printable/Readable Program file Object Program

– nonprintable machine readable file Executable Program

– nonprintable executable code Syntax errors

– reported by the compiler Linker errors

– reported by the linker Execution/Run-time errors

– reported by the operating system Logic errors

– not reported

DATA REPRESENTATION AND STORAGE

Number Systems

Data Types and Storage


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Data Representation and Storage

Digital computers store information as a sequence of bits (binary digits).

The value or state of a bit at any given time can be 0 or 1 (off or on).

Data is stored as a sequence of bytes. – A byte is a sequence of 8 bits.


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Data Representation and Storage:Memory DiagramAddress Sixteen Bit Word

000 0000101011011101

001 1010001011010100

010 1011010010100101

011 0101001101010101

010 0101000111001110

010 1100110000111010

110 0100011101001001

111 0101110001001000


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Address Space = 8Word Size = 16

Data Representation and Storage

Right most bit is referred to as the least significant bit.

Left most bit is referred to as the most significant bit.

Value stored at address 000 is 00001010110111012 = 278110 But what does it

represent?


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Number Systems

Base ten number system• Ten decimal digits (0,1,2,3,4,5,6,7,8,9)

• Each digit multiplies a power of ten

– Example:

24510 = 2*102 + 4*101 + 5*100


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Number Systems

Base two (binary) number system• Two binary digits (0,1)

• Each digit multiplies a power of two

– Example:

101102 = 1*24 + 0*23 + 1*22 + 1*21 + 0*20

= 1*16 + 0*8 + 1*4 + 1*2 + 0*1

= 16 + 0 + 4 + 2 + 0

= 2210


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Number Systems

Base eight number system• Eight octal digits (0,1,2,3,4,5,6,7)

• Each digit multiplies a power of eight

– Example:

2458 = 2*82 + 4*81 + 5*80

= 2*64 + 4*8 + 5*1

= 128 + 32 + 5

= 1658


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Number Systems

Base sixteen number system• Sixteen hex digits (0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F)

• Each digit multiplies a power of sixteen

– Example:

2FB16 = 2*162 + F*161 + B*160

= 2*256 + F*16 + B*1

= 512 + 240 + 11

= 76310


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Number Systems: Practice!

1002 = ?8

37168 = ?2

1101001112 = ?10

3A1B16 = ?2


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Data Types

Integer Data Type:– Often represented in 4 bytes (System

Dependent)– Left most bit is reserved for the sign of the

number– Remaining 31 bits represent the magnitude of

the number.


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Data Types

Representation of data affects the efficiency of arithmetic and logic operations.

For efficiency, negative integers are often represented in their 2’s complement form.

The 2’s complement of an integer is formed by negating all of the bits and adding one.


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Example: 2’s Complement

Form the 2’s complement representation for the value -12710 assuming a word size of 8 for simplicity.12710 = 011111112

Negate bits: 10000000

Add 1: 10000001

2’s complement is 10000001


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Example: 2’s Complement

Add 127 to -12701111111

+10000001

= _______00000000


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Data Types

Floating Point Data– Floating point types represent real numbers,

such as 1.25, that include a decimal point.– Digits to the right of the decimal point form the

fractional part of the number.– Digits to the left of the decimal point form the

integral part of the number.


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Practice! Floating Point Data

Convert 12.2510 to binary.


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AN ENGINEERING PROBLEM-SOLVING METHODOLOGY


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5 Step Problem Solving Methodology1. State the problem clearly.

2. Describe the input and output.

3. Work a hand example.

4. Develop a solution.

5. Test your solution.


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4/23/2015Engineering Problem Solving with C++ second edition, J. ingber 1 Engineering Problem Solving with C++, Etter/Ingber Chapter 1