Class: SPARQL::Algebra::Operator::Floor

Inherits:
Operator::Unary
  • Object
show all
Includes:
Evaluatable
Defined in:
lib/sparql/algebra/operator/floor.rb

Overview

The SPARQL logical floor operator.

[121] BuiltInCall ::= ... 'FLOOR' '(' Expression ')'

Examples:

SPARQL Grammar

PREFIX : <http://example.org/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
SELECT ?s ?num (FLOOR(?num) AS ?floor) WHERE {
 ?s :num ?num
}

SSE

(prefix
 ((: <http://example.org/>)
  (xsd: <http://www.w3.org/2001/XMLSchema#>))
 (project (?s ?num ?floor)
  (extend ((?floor (floor ?num)))
   (bgp (triple ?s :num ?num)))))

See Also:

Constant Summary collapse

NAME = 
[:floor]

Instance Method Summary collapse

Methods included from Evaluatable

#evaluate, #memoize, #replace_aggregate!, #replace_vars!

Instance Method Details

#apply(operand, **options) ⇒ RDF::Literal

Returns the largest (closest to positive infinity) number with no fractional part that is not greater than the value of arg. An error is raised if arg is not a numeric value.

If type of $arg is one of the four numeric types xs:float, xs:double, xs:decimal or xs:integer the type of the result is the same as the type of $arg. If the type of $arg is a type derived from one of the numeric types, the result is an instance of the base numeric type.

For float and double arguments, if the argument is positive zero, then positive zero is returned. If the argument is negative zero, then negative zero is returned.

Parameters:

  • operand (RDF::Literal) —

    the operand

Returns:

  • (RDF::Literal) —

    literal of same type

Raises:

  • (TypeError) —

    if the operand is not a numeric value



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# File 'lib/sparql/algebra/operator/floor.rb', line 41

def apply(operand, **options)
  case operand
    when RDF::Literal::Numeric then operand.floor
    else raise TypeError, "expected an RDF::Literal::Numeric, but got #{operand.inspect}"
  end
end

#to_sparql(**options) ⇒ String

Returns a partial SPARQL grammar for this operator.

Returns:

  • (String) 


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# File 'lib/sparql/algebra/operator/floor.rb', line 53

def to_sparql(**options)
  "FLOOR(#{operands.to_sparql(**options)})"
end