Data Modifiers এবং Math Functions এর ব্যবহার

Submitted by administrator on Mon, 01/02/2012 - 15:41

Chapter 09 - Playing with Data Modifiers and Math Functions

In Chapter 4, "Data Types and Names in C," you learned about several data types, such as char, int, float, and double, in the C language. In this hour, you'll learn about four data modifiers that enable you to have greater control over the data. The C keywords for the four data modifiers are

    signed
    unsigned
    short
    long

You're also going to learn about several mathematical functions provided by the C language, such as

    The sin() function
    The cos() function
    The tan() function
    The pow() function
    The sqrt() function




Summary

In this lesson you've learned the following:

  •     The signed modifier can be used to enable the sign bit for the char and int data types.
  •     All int variables in C are signed by default.
  •     The unsigned modifier can be used to disable the sign bit for the char and int data types.
  •     The memory space taken by a data variable can be reduced or increased by using the short, or long, data modifier respectively.
  •     There is a set of C library functions, such as sin(), cos(), and tan(), that can be used to perform trigonometric or hyperbolic computations.
  •     There is another group of math functions in C—for example, pow()—that can perform exponential and logarithmic calculation.
  •     The sqrt() function returns a non-negative square root. The expression sqrt(x) is equivalent to the pow(x, 0.5) expression, if x has a non-negative value.
  •     The header file math.h must be included in your C program if you call some math functions defined in the header file.


 

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Exercises : Answer the following Question

To help solidify your understanding of this hour's lesson, you are encouraged to answer the quiz questions and finish the exercises provided in the Workshop before you move to the next lesson.

Question and Answer

    Q Why is random access to a disk file necessary?