com.singularsys.jep.functions
Class Binomial
java.lang.Object
com.singularsys.jep.functions.PostfixMathCommand
com.singularsys.jep.functions.BinaryFunction
com.singularsys.jep.functions.Binomial
- All Implemented Interfaces:
- PostfixMathCommandI, java.io.Serializable
public class Binomial
- extends BinaryFunction
Binomial coefficients: binom(n,i).
Requires n,i integers >=0.
Often written as nCi or column vector (n,i).
The following rules apply:
(n,0) = 1, (n,1) = n, (n,n-1) = n, (n,n) = 1
(n,i) = n! / ( i! (n-i)! )
Pascals triangle rule: (n,i) = (n-1,i-1) + (n-1,i)
Binomial theorem: (a+b)^n = sum (n,i) a^i b^(n-i), i=0..n.
For efficiency the binomial coefficients are stored in a static array.
- Author:
- Rich Morris
Created on 13-Feb-2005
- See Also:
- Serialized Form
Method Summary |
static int |
binom(int n,
int i)
Returns the binomial coefficients. |
java.lang.Object |
eval(java.lang.Object l,
java.lang.Object r)
|
Methods inherited from class com.singularsys.jep.functions.PostfixMathCommand |
asArray, asBool, asDouble, asInt, asLong, asStrictInt, asString, checkNumberOfParameters, checkStack, getName, getNumberOfParameters, setCurNumberOfParameters, setName, toString |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Binomial
public Binomial()
eval
public java.lang.Object eval(java.lang.Object l,
java.lang.Object r)
throws EvaluationException
- Specified by:
eval
in class BinaryFunction
- Throws:
EvaluationException
binom
public static int binom(int n,
int i)
throws java.lang.ArrayIndexOutOfBoundsException
- Returns the binomial coefficients.
- Throws:
java.lang.ArrayIndexOutOfBoundsException
- if n<0, i<0 or i>n
Copyright © 2010 Singular Systems http://www.singularsys.com/jep