Numeric literals - Representation of numbers in source code - Perl ABC - Perl Installation, Perl Tutorial, Many Examples

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Numeric literals - Representation of numbers in source code

The representation of numbers in the source code is called number literals . Numeric literals can be written as follows.

integer

Numbers that are not enclosed in quotes or double quotes are interpreted by Perl as numeric literals.

my $num1 = 1;

# Negative number
my $num2 = -1;

Digit separator expression

If an underscore is included in a numeric literal, it will be ignored. The notations 1_000_000 and 1000000 are equivalent. Underscores can be used to make large numbers easier to read.

# You can use _ as a digit separator.
my $num3 = 1_000_000;

Decimal (floating point)

If it contains a. (Dot), it is interpreted as a decimal. It is the same as the notation in mathematics. A few Perls are double precision floating point.

# Decimal point
my $num4 = 1.33;

Minority exponential notation

You can use exponential notation to represent a small number of numbers. 1.3E3 is equivalent to 1300. 1.3E-3 is equivalent to 0.0013.

# 1.3 x 10 cubed
my $num5 = 1.3E3;

# 1.3 x 10 to the -3rd power
my $num6 = 1.3E-3;

Binary number

You can specify a numerical value in binary by prefixing it with 0b.

my $num_bin = 0b1111;

Octal number

If you add 0 to the beginning, you can specify a numerical value in octal.

my $num_oct = 0777;

Hexadecimal

You can specify a number in hexadecimal by prefixing it with 0x.

my $num_hex = 0xFFFF;

What are the numbers in Perl?

The numbers in Perl are explained in detail below.

Handling of numbers in Perl

Example program

This is an example program that uses numerical literals.

use strict;
use warnings;

my $num1 = 1;

# Negative number
my $num2 = -1;

# You can use _ as a digit separator.
my $num3 = 1_000_000;

# Decimal
my $num4 = 1.33;

# Minority exponential notation 1.3 x 10 cubed
my $num5 = 1.3E3;

# 1.3 x 10 to the -3rd power
my $num6 = 1.3E-3;

print "\$num1 = $num1\n";
print "\$num2 = $num2\n";
print "\$num3 = $num3\n";
print "\$num4 = $num4\n";
print "\$num5 = $num5\n";
print "\$num6 = $num6\n";

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