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# jMult -- the j-multiplicity of an ideal

- Usage:
    `jMult(I)`
- Inputs:
  - I, an ideal,
- Outputs:
  - an integer, the j-multiplicity of I

## Description

Given an ideal I, this function computes the j-multiplicity of I following the method of Nishida-Ulrich.

    i1 : R = QQ[x,y,z]

    o1 = R

    o1 : PolynomialRing

    i2 : I = ideal"xy,yz,zx"

    o2 = ideal (x*y, y*z, x*z)

    o2 : Ideal of R

    i3 : elapsedTime jMult I
     -- .0237773s elapsed

    o3 = 2

    i4 : elapsedTime monjMult I
     -- .104795s elapsed

    o4 = 2

    i5 : elapsedTime multiplicitySequence I
     -- .133538s elapsed

    o5 = HashTable{2 => 3}
                   3 => 2

    o5 : HashTable

## See also

- multiplicitySequence -- the multiplicity sequence of an ideal
- monjMult -- j-multiplicity of a monomial ideal

## Ways to use jMult:

- `jMult(Ideal)`

## For the programmer

The object jMult is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/MultiplicitySequence.m2:554:0.