What is the use of truncate methods in Dart?

Dart - Interview Questions

In Dart, the `truncate()` methods are used to truncate a floating-point number to an integer value. Dart provides two methods for truncation:

1. `truncate()` : The `truncate()` method returns the integer obtained by discarding any fractional digits from a floating-point number towards zero.

   double number = 3.8;
   int truncatedNumber = number.truncate();
   print(truncatedNumber);  // Output: 3â€‹

In this example, the `truncate()` method is called on the `number` variable, which has a value of 3.8. The method truncates the decimal part, resulting in an integer value of 3.

2. `truncateToDouble()` : The `truncateToDouble()` method works similarly to `truncate()`, but it returns the result as a `double` instead of an `int`.

   double number = 5.6;
   double truncatedNumber = number.truncateToDouble();
   print(truncatedNumber);  // Output: 5.0â€‹

Here, the `truncateToDouble()` method is used on the `number` variable with a value of 5.6. It truncates the decimal part and returns the result as a `double`, resulting in the value 5.0.

The `truncate()` methods are useful when you want to discard the fractional part of a floating-point number and obtain the integer value. It can be used in various scenarios, such as converting a floating-point number to an integer index or performing calculations where only the whole number portion is relevant.