Category:Definitions/Step Functions

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This category contains definitions related to Step Functions.
Related results can be found in Category:Step Functions.


Definition $1$

A step function is a real function whose graph consists entirely of unconnected horizontal line segments.


Definition $2$

A real function $f: \R \to \R$ is a step function if and only if it can be expressed as a finite linear combination of the form:

\(\ds \map f x\) \(=\) \(\ds \sum_{i \mathop = 1}^n \lambda_i \chi_{\mathbb I_i}\)
\(\ds \) \(=\) \(\ds \lambda_1 \chi_{\mathbb I_1} + \lambda_2 \chi_{\mathbb I_2} + \cdots + \lambda_n \chi_{\mathbb I_n}\)

where:

$\lambda_1, \lambda_2, \ldots, \lambda_n$ are real constants
$\mathbb I_1, \mathbb I_2, \ldots, \mathbb I_n$ are half-open intervals which partition $\R$
$\chi_{\mathbb I_1}, \chi_{\mathbb I_2}, \ldots, \chi_{\mathbb I_n}$ are characteristic functions of $\mathbb I_1, \mathbb I_2, \ldots, \mathbb I_n$.

Subcategories

This category has only the following subcategory.

Pages in category "Definitions/Step Functions"

The following 5 pages are in this category, out of 5 total.