CS 602 – Object Oriented Programming and Software Engineering

Introduction to Computers

The IBM 700/7000 Series… (Circa 1960)

Memory => 4k – 32k ‘words’4000 integer operations/second (Int Op: 15 + 25 = 40)8000 floating point operations/second (Flop: 1.5 + 3.5 = 5.0) Input/Output of 50,000 characters/second

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Typical Desktop ‘PC’

Memory => 128 million => 4 billion characters (1 ‘word’ ≈ 4-6 characters)100,000,000 int ops/second100,000,000 flopsI/O 10,000,000 char/sec

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The CPU

Memory (Main and Secondary)

I/O Devices

Data Representation in a Computer

Bits, Bytes and Words

The Binary Number System (Number Systems in General…) Octal and Hexadecimal Representation of Binary Numbers Types of Data Stored in Memory

o IntegerExample: 15, -35, 2147483647 (231-1)

-2147483648 (-231)o Real (Floating Point)

Characteristic, Mantissa, Range, PrecisionExample: 3.5, -15.25, 1.505E+05

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o Character (See Appendix A)Example: ‘A’, ‘8’, ‘/’, ‘b’

Computer Languages

o Compilers

o Languages => Fortran, C/C++, Basic, Ada, PASCAL, COBOL, Assembler Language, Machine Language, etc.

The History of the Fortran Language (FORmula TRANslation)

Originally developed in 1954-57 by IBM. Continued development through Fortran 95/2003 in use today. FORTRAN (’54-‘57) => FORTRAN II (’58) => FORTRAN IV (‘62) =>FORTRAN ’66 (‘66) => FORTRAN ’77 (’77) => Fortran ’90 (’90) =>Fortran ’95 (’96) => Fortran 2003 (tentative)

The newest standard is for Fortran 2003, which allows Fortran and C/C++ to work together…

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