Triangular function

From Wikipedia, the free encyclopedia

Triangular function
Triangular function

The triangular function (also known as the triangle function, hat function, or tent function) is defined as:

\operatorname{tri}(t) = \and (t) =  \begin{cases} 1 - |t|; & |t| < 1 \\ 0 & \mbox{otherwise}  \end{cases}

or, equivalently, as the convolution of two identical unit rectangular functions:

\operatorname{tri}(t) = \operatorname{rect}(t) * \operatorname{rect}(t)

The function is useful in signal processing and communication systems engineering as a representation of an idealized signal, and as a prototype or kernel from which more realistic signals can be derived. It also has applications in pulse code modulation as a pulse shape for transmitting digital signals and as a matched filter for receiving the signals. It is also equivalent to the triangular window sometimes called the Bartlett window.

The unitary Fourier transforms of the triangular function are:

\frac{1}{\sqrt{2\pi}}\int_{-\infty}^\infty \textrm{tri}(t)e^{-i \omega t} \, dt = \sqrt{2\pi} \left( \frac{\textrm{sinc}(\frac{\omega}{2\pi})}{\sqrt{2\pi}}   \right)^2
=\frac{1}{\sqrt{2\pi}}\cdot \mathrm{sinc}^2\left(\frac{\omega}{2\pi}\right),   in terms of the normalized sinc function
\int_{-\infty}^\infty \mathrm{tri}(t)\cdot e^{-i 2\pi f t} \, dt \  = \ \mathrm{sinc}^2(f)


These results follow from the Fourier transform of the rectangular function, and the convolution property of the Fourier transform.

Advanced Search
Included Web Search Engines


Safe Search

close

Top Matching Results

Occasionally Search.com will highlight specialized results that are based on the context of your query. Examples of specialized results include specific links to news, images, or video.

Top Matching Results may highlight information from other Search.com pages, content from the CNET Network of sites, or third party content. The listings are based purely on relevance. Search.com does not receive payment for listings in this section but our partners that provide this data may get paid for listing these products.

Sponsored Links

This section contains paid listings which have been purchased by companies that want to have their sites appear for specific search terms and related content. These listings are administered, sorted and maintained by a third party and are not endorsed by Search.com.

Search Results

Search.com sends your search query to several search engines at one time and integrates the results into one list which has been sorted by relevance using Search.com's proprietary algorithm. You can customize the list of search engines included in your metasearch from the preferences.

The search engines that are used in your metasearch may allow companies to pay to have their Web sites included within the results. To view the Paid Inclusion policy for a specific search engine, please visit their Web site. Search.com does not accept payment or share revenue with any search engine partner for listings in this section.