Add Split A Float Into Its Integer And Decimal as a Ruby TIL

ruby/split-a-float-into-its-integer-and-decimal.md

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+# Split A Float Into Its Integer And Decimal
+
+Let's say we have a float value like `3.725`. We want to break it up into its
+constituent parts -- the integer part (`3`) and the decimal part (`0.725`).
+
+This can be done with the `divmod` method on the `Numeric` class.
+
+```ruby
+3.725.divmod(1)
+=> [3, 0.7250000000000001]
+```
+
+In the general case, this method gives you the quotient and the modulus of
+dividing the number by the given value. When that given value is specifically
+`1`, it will give you those two parts of the float.
+
+One place where this might be useful is when trying to convert a float
+representing an amount of time into hours and minutes.
+
+```ruby
+hours = 3.725
+
+hours_digit, percentage_minutes = hours.divmod(1)
+
+minutes = (60 * percentage_minutes).to_i
+hours_standard = "#{hours_digit}:#{minutes}"
+```
+
+[source](https://ruby-doc.org/core-2.5.3/Numeric.html#method-i-divmod)