A stream manipulator that displays floating point numbers in fixed-point notation

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What are stream manipulators?
Which stream manipulator can be used to display Boolean values as strings?
What is parameterized manipulators in C++?
What are the various manipulators available in C++?

Flag Name Corresponding
Stream Manipulator Description ios::fixed fixed if this is set, floating point numbers are printed in fixed-point notation. When this flag is set, ios::scientific is automatically unset ios::scientific scientific if this is set, floating point numbers are printed in scientific (exponential) notation. When this flag is set, ios::fixed is automatically unset ios::showpoint showpoint if this is set, the decimal point is always shown, even if there is no precision after the decimal. Can be unset with the manipulator noshowpoint ios::showpos showpos if set, positive values will be preceded by a plus sign + . Can be unset with the manipulator noshowpos. ios::right right if this is set, output items will be right-justified within the field (when using width() or setw()), and the unused spaces filled with the fill character (the space, by default). ios::left left if this is set, output items will be left-justified within the field (when using width() or setw()), and the unused spaces filled with the fill character (the space, by default). ios::showbase showbase Specifies that the base of an integer be indicated on the output. Decimal numbers have no prefix. Octal numbers (base 8) are prefixed with a leading 0. Hexadecimal numbers (base 16) are prefixed with a leading 0x. This setting can be reset with the manipulator noshowbase. ios::uppercase uppercase specifies that the letters in hex outputs (a-f) and the letter 'e' in scientific notation will be output in uppercase. This can be reset with the manipulator nouppercase.

Manip.RngDescription General output endlnow Write a newline ('\n') and flush buffer. setw(n)next Sets minimum field width on output. This sets the minimum size of the field - a larger number will use more columns. Applies only to the next element inserted in the output. Use left and right to justify the data appropriately in the field. Output is right justified by default. Equivalent to cout.width(n); To print a column of right justified numbers in a seven column field:

    cout << setw(7) << n << endl;

width(n)next Same as setw(n). leftnext Left justifies output in field width. Only useful after setw(n). rightnext Right justifies output in field width. Since this is the default, it is only used to override the effects of left. Only useful after setw(n).

    cout << setw(4) << setfill('0') << n << endl;

3all Only useful after

    cout << setw(4) << setfill('0') << n << endl;

4. If a value does not entirely fill a field, the character ch will be used to fill in the other characters. Default value is blank. Same effects as

    cout << setw(4) << setfill('0') << n << endl;

5 For example, to print a number in a 4 character field with leading zeros (eg, 0007):

    cout << setw(4) << setfill('0') << n << endl;

Floating point output

    cout << setw(4) << setfill('0') << n << endl;

6all Sets the number of digits printed to the right of the decimal point. This applies to all subsequent floating point numbers written to that output stream. However, this won't make floating-point "integers" print with a decimal point. It's necessary to use

    cout << setw(4) << setfill('0') << n << endl;

7 for that effect. Equivalent to cout.precision(n);

    cout << setw(4) << setfill('0') << n << endl;

7all Used fixed point notation for floating-point numbers. Opposite of

    cout << setw(4) << setfill('0') << n << endl;

9. If no precision has already been specified, it will set the precision to 6.

    cout << setw(4) << setfill('0') << n << endl;

9all Formats floating-point numbers in scientific notation. Opposite of

    cout << setw(4) << setfill('0') << n << endl;

7. endl2 output endl3all Uses alphabetic representation (endl4 and endl5) for endl2 values. Turned off with endl7. Input endl8
endl9all For most input values (eg, integers and floating-point numbers), skipping initial whitespace (eg, blanks) is very useful. However, when reading characters, it is often desired to read the whitespace characters as well as the non-spacing characters. The these I/O manipulators can be used to turn whitespace skipping off and on. Eg,
setw(n)0
turns whitespace skipping off for all subseqent setw(n)1 input. setw(n)2now Reads and ignores whitespace at the current position. Other showpoint, noshowpoint, uppercase, nouppercase, dec, oct, hex, setbase(8|10|16), showbase, noshowbase, ends, showpos, noshowpos, internal, flush, unitbuf, nounitbuf, setiosflags(f), resetiosflags(f)

What are stream manipulators?

Manipulators are special functions that can be included in the I/O statement to alter the format parameters of a stream. Manipulators are operators that are used to format the data display. To access manipulators, the file iomanip. h should be included in the program.

Which stream manipulator can be used to display Boolean values as strings?

3. Stream manipulator boolalpha sets the output stream to display bool values as the strings "true" and "false".

What is parameterized manipulators in C++?

Parameterized manipulators are manipulators that take one or more parameters. Because manipulators are ordinary identifiers, and therefore use up possible names, iostream doesn't define them for every possible function. A number of manipulators are discussed with member functions in other parts of this chapter.