C Libraries: math and cytpe

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C Libraries math and cytpe

• Lecture 15 Mon, Sep 29, 2003

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C Libraries

• A library is a collection of related functions
  that have been compiled and stored in a .lib
  file.
• C provides an extensive collection of
  libraries.
• A library file may be added to a CodeWarrior
  project and linked to a program.
• The corresponding header file should be included
  in the program.

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The math Library

• The math library contains most of the standard
  mathematical functions.
• Include ltcmathgt in the .cpp file in which the
  functions are used.
• A common error is to use a math function, but
  forget to include ltcmathgt.

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The math Functions

• double cos(double x)
• Return cos x.
• double sin(double x)
• Return sin x.
• double tan(double x)
• Return tan x.

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The math Functions

• double acos(double x)
• Return arccos x.
• double asin(double x)
• Return arcsin x.

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The math Functions

• double atan(double x)
• Return arctan x in the range
• ?/2 lt arctan x lt ?/2.
• double atan2(double y, double x)
• Return arctan y/x in the range
• ? lt arctan y/x ?.

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The math Functions

• double cosh(double x)
• Return cosh x.
• double sinh(double x)
• Return sinh x.
• double tanh(double x)
• Return tanh x.

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The math Functions

• double exp(double x)
• Return ex (natural base e 2.71828...).
• double log(double x)
• Return ln x (natural base e 2.71828...).
• double log10(double x)
• Return log x (base 10).

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The math Functions

• double pow(double x, double y)
• Get x raised to the y power.
• double sqrt(double x)
• Get the square root of x.

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The math Functions

• double ceil(double x)
• Get the integer n such that n 1 lt x n
• double floor(double x)
• Get the integer n such that n x lt n 1.

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Examples of Math Functions

• FinancialPlanner.cpp
• Surveyor1.cpp
• Surveyor2.cpp

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The ctype Library

• The ctype library contains functions that
  facilitate the manipulation of characters.
• Include ltcctypegt in the .cpp file in which the
  functions are used.
• These functions return int because int was the
  old-style bool (0 is false, ? 0 is true).

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The ctype Functions

• int isalpha(int c)
• Determine whether the specified character c is an
  uppercase or a lowercase letter.
• int isdigit(int c)
• Determine whether the specified character c is a
  digit.

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The ctype Functions

• int isupper(int c)
• Determine whether the specified character c is an
  uppercase letter.
• int islower(int c)
• Determine whether the specified character c is a
  lowercase letter.

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The ctype Functions

• int tolower(int c)
• Get the lowercase equivalent of the specified
  character c if c is an uppercase letter. The
  character c is returned if c is not an uppercse
  letter.
• int toupper(int c)
• Get the uppercase equivalent of the specified
  character c if c is a lowercase letter. The
  character c is returned if c is not a lowercase
  letter.

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The ctype Functions

• int isalnum(int c)
• Determine whether the specified character c is an
  uppercase or a lowercase letter or a digit.
• int ispunct(int c)
• Determine whether the specified character c is a
  punctuation character.

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The ctype Functions

• int isspace(int c)
• Determine whether the specified character c is
  white space (space, newline, tab, form feed).
• int iscntrl(int c)
• Determine whether the specified character c is a
  control character.

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The ctype Functions

• int isgraph(int c)
• Determine whether the specified character c is a
  graphics character.
• int isprint(int c)
• Determine whether the specified character c is a
  printable character.

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The ctype Functions

• int isxdigit(int c)
• Determine whether the specified character c is a
  hexadecimal digit (0 - 9, a - f, A - F).

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Examples of ctype Functions

• Validator.cpp