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Functions ( Q; |9 ]1 M4 k% cFourier Transform q% i3 P3 N+ X# _fft Fast Fourier transform* q7 |5 v& F$ a
fft2 2-D fast Fourier transform7 w- x! I& ?. G' a% g
fftn N-D fast Fourier transform9 C/ ~8 s3 B9 e; N* F7 R" [
fftshift Shift zero-frequency component to center of spectrum7 t' D" i: T, r- Y: X: c
fftw Define method for determining FFT algorithm# J5 C: h9 x" Q# x# [
ifft Inverse fast Fourier transform & d! h, u9 l4 }ifft2 2-D inverse fast Fourier transform& S% ^/ ?% g( V. ^3 r
ifftn Multidimensional inverse fast Fourier transform6 l, B$ n; m, O
ifftshift Inverse zero-frequency shift5 y i* n8 l5 y( O
nextpow2 Exponent of next higher power of 2 9 ]- ] ^( \* J$ ginterpft 1-D interpolation (FFT method)% ^( P* q0 c3 @8 Z; F3 R+ u
Convolution $ |6 Q8 N) i. ^conv Convolution and polynomial multiplication + |, j# N7 p' R8 Z1 @* k! z1 Lconv2 2-D convolution' E1 X$ e6 q# L
convn N-D convolution 2 @( U/ c7 G5 n4 Z# X, g% odeconv Deconvolution and polynomial division) h0 J! N- J3 l0 O$ V! K
Digital Filtering& Q* s8 V+ L3 q# g
filter 1-D digital filter' O/ z- j( }) k) _
filter2 2-D digital filter $ ]! B* M9 ]% N' `& r, l) Jss2tf Convert state-space representation to transfer function , f& n# J$ \# _; Ipadecoef Padé approximation of time delays/ R' S! X X4 i$ m! }; ?
Topics % g6 t8 w3 m, _Fourier Transforms ' Y- \$ n* A( R3 ]9 C, X9 x6 j6 j; t5 v9 |; S" V, g9 d
$ b$ M* d5 I! t& h) v4 t2 CThe Fourier transform is a powerful tool for analyzing data across many applications, including Fourier analysis for signal processing. 2 [. H% j3 f* b) e: h! `. H9 I: L2 f3 J* T5 c6 O( E( ~
7 Q0 v' p# C8 w1 Z* k5 f! z& f3 xTransform 2-D optical data into frequency space. 8 D. B6 R) k. [* B" N( U- B& U2 \ o3 r) S h) F8 l/ f; u, p; h) D# G$ h9 n: Z8 ]! ~+ X* T p! U& `; D
Smooth Data with Convolution 5 y0 z& O; r2 a! r, O" r& V 6 ~1 J0 G$ p5 }) M- J5 ?6 ~: Q) m9 w/ M* I! i9 y4 Q9 T0 A% B
Smooth noisy, 2-D data using convolution.5 ^5 N" F/ I, ]/ t ^5 [ ]7 i ~
8 n' Q8 a$ ]: D% B" G( k6 ~) m2 L5 s $ z, ?4 v( |& i2 p$ nFilter Data % D% f: U- d+ M3 p0 q' P2 E% e 8 {* K: F4 t6 o0 X# g4 v* Y! I( t3 _4 G# ]/ l& c" c& ` i1 o
Filtering is a data processing technique used for smoothing data or modifying specific data characteristics, such as signal amplitude. 0 y1 {) m+ c; x 0 t6 C s) ]5 `6 a- @. z0 _+ J# D! V$ E* j
到此为止，上面的每一个函数都可以通过在MATLAB的命令窗口中输入：, |" E+ h1 [- v2 T
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doc 你要搜索的函数名; V# p( f0 E; S" L* v: k2 M
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/ N2 l! K3 q0 r得到相应的函数介绍。3 ]6 [; ~3 q% Y8 B& L& w
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