Transforms | Fourier analysis

Non-uniform discrete Fourier transform

In applied mathematics, the nonuniform discrete Fourier transform (NUDFT or NDFT) of a signal is a type of Fourier transform, related to a discrete Fourier transform or discrete-time Fourier transform, but in which the input signal is not sampled at equally spaced points or frequencies (or both). It is a generalization of the shifted DFT. It has important applications in signal processing, magnetic resonance imaging, and the numerical solution of partial differential equations. As a generalized approach for nonuniform sampling, the NUDFT allows one to obtain frequency domain information of a finite length signal at any frequency. One of the reasons to adopt the NUDFT is that many signals have their energy distributed nonuniformly in the frequency domain. Therefore, a nonuniform sampling scheme could be more convenient and useful in many digital signal processing applications. For example, the NUDFT provides a variable spectral resolution controlled by the user. (Wikipedia).

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The Two-Dimensional Discrete Fourier Transform

The two-dimensional discrete Fourier transform (DFT) is the natural extension of the one-dimensional DFT and describes two-dimensional signals like images as a weighted sum of two dimensional sinusoids. Two-dimensional sinusoids have a horizontal frequency component and a vertical frequen

From playlist Fourier

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Effects of signal nonstationarities on the Fourier power spectrum

This is part of an online course on foundations and applications of the Fourier transform. The course includes 4+ hours of video lectures, pdf readers, exercises, and solutions. Each of the video lectures comes with MATLAB code, Python code, and sample datasets for applications. With 3000

From playlist Understand the Fourier transform

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Fourier Transforms: Discrete Fourier Transform, Part 3

Data Science for Biologists Fourier Transforms: Discrete Fourier Transform Part 3 Course Website: data4bio.com Instructors: Nathan Kutz: faculty.washington.edu/kutz Bing Brunton: faculty.washington.edu/bbrunton Steve Brunton: faculty.washington.edu/sbrunton

From playlist Fourier

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The Discrete Fourier Transform

This video provides a basic introduction to the very widely used and important discrete Fourier transform (DFT). The DFT describes discrete-time signals as a weighted sum of complex sinusoid building blocks and is used in applications such as GPS, MP3, JPEG, and WiFi.

From playlist Fourier

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Discrete Fourier Transform - Example

We do a very simple example of a Discrete Fourier Transform by hand, just to get a feel for it. We quickly realize that using a computer for this is a good idea...

From playlist Mathematical Physics II Uploads

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Introduction to the z-Transform

http://AllSignalProcessing.com for more great signal processing content, including concept/screenshot files, quizzes, MATLAB and data files. Introduces the definition of the z-transform, the complex plane, and the relationship between the z-transform and the discrete-time Fourier transfor

From playlist The z-Transform

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Discrete Fourier Transform - Introduction

An introduction to the Discrete Fourier Transform (DFT) and its interpretation.

From playlist Mathematical Physics II Uploads

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Fourier Transforms: Discrete Fourier Transform, Part 2

Data Science for Biologists Fourier Transforms: Discrete Fourier Transform Part 2 Course Website: data4bio.com Instructors: Nathan Kutz: faculty.washington.edu/kutz Bing Brunton: faculty.washington.edu/bbrunton Steve Brunton: faculty.washington.edu/sbrunton

From playlist Fourier

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Discrete Fourier Transform - Simple Step by Step

Easy explanation of the Fourier transform and the Discrete Fourier transform, which takes any signal measured in time and extracts the frequencies in that signal. This is a work in progress, let me know if anything doesn't make sense, and I will update the video to make that clearer. Tha

From playlist Fourier

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Nicki Holighaus: Time-frequency frames and applications to audio analysis - Part 1

Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Mathematics Library: http://library.cirm-math.fr. And discover all its functionalities: - Chapter markers and keywords to watch the parts of your choice in the video - Videos enriched with abstracts, b

From playlist Analysis and its Applications

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"Magnetic Edge and Semiclassical Eigenvalue Asymptotics" by Dr. Ayman Kachmar

What will be the energy levels of an electron moving in a magnetic field? In a typical setting, these are eigenvalues of a special magnetic Laplace operator involving the semiclassical parameter (a very small parameter compared to the sample’s scale), and the foregoing question becomes on

From playlist CAMS Colloquia

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Structured Regularization Summer School - A.Hansen - 1/4 - 19/06/2017

Anders Hansen (Cambridge) Lectures 1 and 2: Compressed Sensing: Structure and Imaging Abstract: The above heading is the title of a new book to be published by Cambridge University Press. In these lectures I will cover some of the main issues discussed in this monograph/textbook. In par

From playlist Structured Regularization Summer School - 19-22/06/2017

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Suhasini Subba Rao: Fourier based methods for spatial data observed on irregularly spaced locations

Abstract : In this talk we introduce a class of statistics for spatial data that is observed on an irregular set of locations. Our aim is to obtain a unified framework for inference and the statistics we consider include both parametric and nonparametric estimators of the spatial covarianc

From playlist Probability and Statistics

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21. Sampling

MIT MIT 6.003 Signals and Systems, Fall 2011 View the complete course: http://ocw.mit.edu/6-003F11 Instructor: Dennis Freeman License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu

From playlist MIT 6.003 Signals and Systems, Fall 2011

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Incidence Theory and Uniform Distribution in Higher Dimensions - Alex Iosevich

Special Year Research Seminar Topic: Incidence Theory and Uniform Distribution in Higher Dimensions Speaker: Alex Iosevich Affiliation: University of Rochester Date: February 14, 2023 2:00pm Simonyi Hall 101 Incidence bound for points and spheres in higher dimensions generally becomes tr

From playlist Mathematics

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The Discrete Fourier Transform: Most Important Algorithm Ever?

Go to https://nordvpn.com/reducible to get the two year plan with an exclusive deal PLUS 1 bonus month free! It’s risk free with NordVPN’s 30 day money back guarantee! The Discrete Fourier Transform (DFT) is one of the most essential algorithms that power modern society. In this video, we

From playlist Fourier

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Guo Chuang Thiang: What is a Coarse Index, physically?

Talk in Global Noncommutative Geometry Seminar, May 4, 2022

From playlist Global Noncommutative Geometry Seminar (Europe)

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Spectra of metric graphs and crystalline measures - Peter Sarnak

Members' Seminar Topic: Spectra of metric graphs and crystalline measures Speaker: Peter Sarnak Affiliation: Professor, School of Mathematics Date: February 10, 2020 For more video please visit http://video.ias.edu

From playlist Mathematics

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Roland Bauerschmidt: Lecture #3

This is a third lecture on "Log-Sobolev inequality and the renormalisation group" by Dr. Roland Bauerschmidt. For more materials and slides visit: https://sites.google.com/view/oneworld-pderandom/home

From playlist Summer School on PDE & Randomness

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The Fourier Transform and Derivatives

This video describes how the Fourier Transform can be used to accurately and efficiently compute derivatives, with implications for the numerical solution of differential equations. Book Website: http://databookuw.com Book PDF: http://databookuw.com/databook.pdf These lectures follow

From playlist Fourier

Related pages

Least-squares spectral analysis | Digital signal processing | Z-transform | Generalized Fourier series | Gaussian elimination | Digital filter | Discrete-time Fourier transform | Fourier transform | Unevenly spaced time series | Fast Fourier transform | Discrete Fourier transform