HomeSearch | ## Ruby Number Examples: Integer, Float, zero and eqlUse numbers and the zero and eql methods. Convert strings into Integers and Floats. | |

## Numbers.Inside, the cave is still. Lights appear upon the cold dark surface wall. Each light is on or off (like a bit, which is set or not set). The lights could represent numbers. | ||

## Ruby examples.Numeric types and conversions are done in Ruby code (not usually in caves). Many programs use the Integer and Float built-in methods. | ||

## Integer, Float.Here we convert string data to number types. A string may contain digits but not be a number. With the Integer conversion, we convert it to one. We also use Float.
| Ruby program that converts strings, numbers
# Two strings with numeric contents.
value1 = "1234"
value2 = "1234.5678"
# Convert strings to numbers.
number1 = Integer(value1)
number2 = Float(value2)
# Print numbers.
print "Number1: ", number1, "\n"
print "Number2: ", number2, "\n"
# Add numbers together.
# ... Could not be done with strings.
number3 = number1 + number2
# Print final number.
print "Number3: ", number3, "\n"
Output
Number1: 1234
Number2: 1234.5678
Number3: 2468.5678 | |

## Exponents.We can directly use exponents, with the two-star operator. In this program, we raise a value to the power of two, and then to the power of three.
| Ruby program that uses exponents
# An initial value.
value = 3
# Square the value.
square = value ** 2
# Cube the value.
cube = value ** 3
# Display our results.
puts square
puts cube
Output
9
27 | |

## Zero, nonzero.Zero() returns true or false. If the number is zero, it returns true. Otherwise, it returns false. Nonzero meanwhile returns the original number if it is not zero.
| Ruby program that uses zero, nonzero
value = 0
if value.zero?
puts "A"
end
if value.nonzero?
puts "B" # Not reached.
end
value = 1
if value.nonzero?
puts "C"
end
Output
A
C | |

## Eql operator.Unlike the "==" operator, eql compares types. So a floating point number, like 1.0, is not equal to an Integer number like 1. The == operator treats them as equal.
| Ruby program that uses eql
value1 = 1
value2 = 1.0
value3 = 1
if value1.eql? value2
puts "A" # Not reached.
end
if value1 == value2
puts "B"
end
if value1.eql? value3
puts "C"
end
Output
B
C | |

## Random numbers.With the rand method we generate a pseudo-random number. The srand method is used to seed our random number generator.rand | ||

## Math.Some numeric operations can be done directly, with operators like + or minus. But many math methods exist, included for easy access. These handle more complex things like sqrt.Math | ||

## A summary.Tasks that involve numbers are often language-specific. In Ruby, we have many helpful operators available on numbers. We convert and manipulate numbers with ease. | ||

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