This arithmetic predicate calculates the smallest integer not smaller than it's argument, i.e. it rounds up if the argument is a positive number. If the argument is a negative number then it rounds down (towards zero). This predicate attempts to convert the result value to an integer.
| Example | |
| X is ceiling( 2.6 ). | The result is X = 3. |
| X is ceiling( 2.1 ). | The result is X = 3. |
| X is ceiling( -2.1). | The result is X = -2. |
| Exceptions | |
| overflow of result | an evaluation_error(float_overflow) exception is thrown |
see also: is/2 arithmetic in Prolog