Sams Teach Yourself C++ in 21 Days

ios::showpoint. TABLE17.1 shows some of the flags you can use. When using these

flags, you need to include iostreamin your listing. In addition, for those flags that

require parameters, you need to include iomanip.

TABLE17.1 Some of the iostreamSet Flags

Flag Purpose

showpoint Displays a decimal point and trailing zeros as required by precision

showpos Turns on the plus sign (+) before positive numbers

left Aligns output to the left

right Aligns output to the right

internal Aligns the sign for a number to the left and aligns the value to the right

showpoint Adds trailing zeros as required by the precision

showpos Displays a plus sign (+) if the number is positive

scientific Shows floating-point values in scientific notation

fixed Shows floating-point numbers in decimal notation

showbase Adds “0x” in front of hexadecimal numbers to indicate that it is a

hexadecimal value

Uppercase Shows hexadecimal and scientific numbers in uppercase

dec Sets the base of the numbers for display to decimal

oct Sets the base of the numbers for display to octal—base 8

hex Sets the base of the numbers for display to hexadecimal—base 16

The flags in Table 17.1 can also be concatenated into the insertion operator. Listing

17.14 illustrates these settings. As a bonus, Listing 17.14 also introduces the setwmanip-

ulator, which sets the width but can also be concatenated with the insertion operator.

LISTING17.14 Using setf

0: // Listing 17.14 - Using setf

1: #include <iostream>

2: #include <iomanip>

3: using namespace std;

4:

5: int main()

6: {

7: const int number = 185;

8: cout << “The number is “ << number << endl;

9:

10: cout << “The number is “ << hex << number << endl;

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