org.apache.pig.piggybank.evaluation.math
Class SIGNUM

java.lang.Object
  extended by org.apache.pig.EvalFunc<Double>
      extended by org.apache.pig.piggybank.evaluation.math.SIGNUM

public class SIGNUM
extends EvalFunc<Double>

math.SIGNUM implements a binding to the Java function Math.signum(double). Given a single data atom it Returns the signum function of the argument.

Parameters:
value - Double.
Return Value:
Double
Return Schema:
SIGNUM_inputSchema
Example:
register math.jar;
A = load 'mydata' using PigStorage() as ( float1 );
B = foreach A generate float1, math.SIGNUM(float1);

Author:
ajay garg
See Also:
Math.signum(double),

Field Summary
 
Fields inherited from class org.apache.pig.EvalFunc
log, pigLogger, reporter, returnType
 
Constructor Summary
SIGNUM()
           
 
Method Summary
 Double exec(Tuple input)
          java level API
 List<FuncSpec> getArgToFuncMapping()
           
 Schema outputSchema(Schema input)
           
 
Methods inherited from class org.apache.pig.EvalFunc
finish, getLogger, getPigLogger, getReporter, getReturnType, getSchemaName, isAsynchronous, progress, setPigLogger, setReporter, warn
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SIGNUM

public SIGNUM()
Method Detail

exec

public Double exec(Tuple input)
            throws IOException
java level API

Specified by:
exec in class EvalFunc<Double>
Parameters:
input - expects a single numeric DataAtom value
output - returns a single numeric DataAtom value, signum function of the argument
Returns:
result, of type T.
Throws:
IOException

outputSchema

public Schema outputSchema(Schema input)
Overrides:
outputSchema in class EvalFunc<Double>
Parameters:
input - Schema of the input
Returns:
Schema of the output

getArgToFuncMapping

public List<FuncSpec> getArgToFuncMapping()
                                   throws FrontendException
Overrides:
getArgToFuncMapping in class EvalFunc<Double>
Returns:
A List containing FuncSpec objects representing the Function class which can handle the inputs corresponding to the schema in the objects
Throws:
FrontendException


Copyright © ${year} The Apache Software Foundation