KroneckerDelta
KroneckerDelta[n1,n2,…]
gives the Kronecker delta , equal to 1 if all the are equal, and 0 otherwise.
Details
- KroneckerDelta[0] gives 1; KroneckerDelta[n] gives 0 for other numeric n.
- KroneckerDelta has attribute Orderless.
- An empty template can be entered as kd. Arguments in the subscript should be separated by commas.
- The comma can be made invisible by using the character \[InvisibleComma] or ,.
- KroneckerDelta automatically threads over lists. »
Examples
open allclose allBasic Examples (4)
Scope (26)
Numerical Evaluation (6)
KroneckerDelta always returns an exact result irrespective of the precision of the input:
Evaluate efficiently at high precision:
Compute the elementwise values of an array using automatic threading:
Or compute the matrix KroneckerDelta function using MatrixFunction:
Compute average-case statistical intervals using Around:
Specific Values (3)
Visualization (3)
Plot the single-argument KroneckerDelta using integer-width bins:
Visualize KroneckerDelta over the reals. Except for a jump at , it is indistinguishable from a zero function:
Plot KroneckerDelta in three dimensions:
Function Properties (10)
KroneckerDelta is defined for all real and complex inputs:
Function range of KroneckerDelta:
The function range for complex values is the same:
KroneckerDelta accepts list inputs:
The traditional notation is used in both StandardForm and TraditionalForm:
KroneckerDelta is not an analytic function:
It has both singularities and discontinuities:
KroneckerDelta is neither nondecreasing nor nonincreasing:
KroneckerDelta is not injective:
KroneckerDelta is not surjective:
KroneckerDelta is non-negative:
KroneckerDelta is neither convex nor concave:
Differentiation and Integration (4)
First derivative with respect to :
Series expansion at a generic point:
Compute the indefinite integral using Integrate:
Applications (5)
Use in sums to pick out terms:
Generate a banded matrix with two superdiagonals:
Compute MoebiusMu using KroneckerDelta and LiouvilleLambda:
Decompose a spherical harmonic into a sum of products of two spherical harmonics:
Properties & Relations (2)
Possible Issues (2)
KroneckerDelta can stay unevaluated for numeric arguments:
A larger setting for $MaxExtraPrecision can be needed:
Equality testing of the arguments takes numerical precision into account:
Text
Wolfram Research (1999), KroneckerDelta, Wolfram Language function, https://reference.wolfram.com/language/ref/KroneckerDelta.html (updated 2017).
CMS
Wolfram Language. 1999. "KroneckerDelta." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2017. https://reference.wolfram.com/language/ref/KroneckerDelta.html.
APA
Wolfram Language. (1999). KroneckerDelta. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/KroneckerDelta.html