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Coiflet

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Coiflet is a discrete wavelet designed by Ingrid Daubechies to be more symmetrical than the Daubechies wavelet. Whereas Daubechies wavelets have vanishing moments, Coiflet scaling functions have zero moments and their wavelet functions have . They are named in honor of Ronald Coifman, who first requested them.

Coiflet coefficients

Both the scaling function (low-pass filter) and the wavelet function (High-Pass Filter) must be normalised by a factor . Below are the coefficients for the scaling functions for C6-30. The wavelet coefficients are derived by reversing the order of the scaling function coefficients and then reversing the sign of every second one. (ie. C6 wavelet = {−0.022140543057, 0.102859456942, 0.544281086116, −1.205718913884, 0.477859456942, 0.102859456942}) Mathematically, this looks like where k is the coefficient index, B is a wavelet coefficient and C a scaling function coefficient. N is the wavelet index, ie 6 for C6.

Coiflets coefficients
k C6 C12 C18 C24 C30
0 −0.102859456942 0.023175193479 −0.005364837341 0.001261922093 −0.000000134600
1 0.477859456942 −0.058640275960 0.011006253418 −0.002304449705 −0.000000236800
2 1.205718913884 −0.095279180620 0.033167120958 −0.010389048053 0.000002918600
3 0.544281086116 0.546042093070 −0.093015528958 0.022724918488 0.000005281600
4 −0.102859456942 1.149364787715 −0.086441527120 0.037734470756 −0.000030144000
5 −0.022140543057 0.589734387392 0.573006670549 −0.114928468858 −0.000058464200
6 −0.108171214184 1.122570513741 −0.079305297034 0.000198755200
7 −0.084052960922 0.605967143547 0.587334781789 0.000427459600
8 0.033488820325 −0.101540281510 1.106252905125 −0.000902454000
9 0.007935767225 −0.116392501524 0.614314652395 −0.002351644400
10 −0.002578406712 0.048868188642 −0.094225477729 0.003441309400
11 −0.001019010797 0.022458481925 −0.136076254102 0.009566002800
12 −0.012739202022 0.055627280306 −0.012960180000
13 −0.003640917832 0.035471674876 −0.027947375800
14 0.001580410202 −0.021512637034 0.046221554000
15 0.000659330348 −0.008002025773 0.058391759000
16 −0.000100385550 0.005305331892 −0.149304477801
17 −0.000048931468 0.001791189058 −0.087732101600
18 −0.000833001142 0.619413698002
19 −0.000367659537 1.095010858804
20 0.000088160707 0.596184647002
21 0.000044165714 −0.073600147200
22 −0.000004609884 −0.129994525601
23 −0.000002524350 0.039835608600
24 0.033104132800
25 −0.014327563800
26 −0.005882221600
27 0.003080491400
28 0.000507122400
29 −0.000299927600