Preface |
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xiii | |
Sample Courses |
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xv | |
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1 | (92) |
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3 | (4) |
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1.1 Fourier's Bold Conjecture |
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3 | (2) |
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1.2 Mathematical Preliminaries and the Following Chapters |
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5 | (2) |
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6 | (1) |
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2 Basic Terminology, Notation and Conventions |
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7 | (8) |
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7 | (1) |
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2.2 Functions, Formulas and Variables |
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8 | (4) |
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2.3 Operators and Transforms |
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12 | (3) |
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3 Basic Analysis I: Continuity and Smoothness |
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15 | (22) |
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15 | (7) |
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22 | (3) |
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3.3 Basic Manipulations and Smoothness |
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25 | (2) |
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27 | (10) |
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34 | (3) |
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4 Basic Analysis II: Integration and Infinite Series |
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37 | (12) |
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37 | (4) |
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4.2 Infinite Series (Summations) |
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41 | (8) |
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48 | (1) |
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5 Symmetry and Periodicity |
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49 | (8) |
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5.1 Even and Odd Functions |
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49 | (2) |
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51 | (2) |
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53 | (4) |
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56 | (1) |
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6 Elementary Complex Analysis |
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57 | (16) |
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57 | (2) |
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6.2 Complex-Valued Functions |
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59 | (2) |
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6.3 The Complex Exponential |
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61 | (5) |
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6.4 Functions of a Complex Variable |
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66 | (7) |
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71 | (2) |
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7 Functions of Several Variables |
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73 | (20) |
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73 | (5) |
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7.2 Single Integrals of Functions with Two Variables |
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78 | (4) |
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82 | (2) |
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7.4 Addenda: Proving Theorems 7.7 and 7.9 |
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84 | (9) |
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90 | (3) |
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93 | (156) |
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8 Heuristic Derivation of the Fourier Series Formulas |
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95 | (6) |
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95 | (1) |
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96 | (3) |
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99 | (2) |
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100 | (1) |
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9 The Trigonometric Fourier Series |
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101 | (20) |
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9.1 Defining the Trigonometric Fourier Series |
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101 | (6) |
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9.2 Computing the Fourier Coefficients |
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107 | (8) |
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9.3 Partial Sums and Graphing |
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115 | (6) |
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117 | (4) |
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10 Fourier Series over Finite Intervals (Sine and Cosine Series) |
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121 | (8) |
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10.1 The Basic Fourier Series |
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121 | (2) |
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10.2 The Fourier Sine Series |
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123 | (2) |
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10.3 The Fourier Cosine Series |
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125 | (1) |
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126 | (3) |
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127 | (2) |
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11 Inner Products, Norms and Orthogonality |
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129 | (16) |
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129 | (2) |
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11.2 The Norm of a Function |
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131 | (1) |
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11.3 Orthogonal Sets of Functions |
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132 | (2) |
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11.4 Orthogonal Function Expansions |
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134 | (1) |
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11.5 The Schwarz Inequality for Inner Products |
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135 | (2) |
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137 | (8) |
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141 | (4) |
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12 The Complex Exponential Fourier Series |
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145 | (10) |
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145 | (2) |
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12.2 Notation and Terminology |
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147 | (2) |
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12.3 Computing the Coefficients |
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149 | (1) |
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150 | (5) |
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151 | (4) |
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13 Convergence and Fourier's Conjecture |
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155 | (24) |
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13.1 Pointwise Convergence |
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155 | (6) |
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13.2 Uniform and Nonuniform Approximations |
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161 | (8) |
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169 | (4) |
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13.4 The Sine and Cosine Series |
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173 | (6) |
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175 | (4) |
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14 Convergence and Fourier's Conjecture: The Proofs |
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179 | (22) |
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14.1 Basic Theorem on Pointwise Convergence |
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179 | (7) |
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14.2 Convergence for a Particular Saw Function |
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186 | (9) |
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14.3 Convergence for Arbitrary Saw Functions |
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195 | (1) |
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14.4 A Divergent Fourier Series |
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196 | (5) |
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15 Derivatives and Integrals of Fourier Series |
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201 | (18) |
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15.1 Differentiation of Fourier Series |
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201 | (5) |
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15.2 Differentiability and Convergence |
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206 | (4) |
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15.3 Integrating Periodic Functions and Fourier Series |
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210 | (4) |
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15.4 Sine and Cosine Series |
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214 | (5) |
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216 | (3) |
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219 | (30) |
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16.1 The Heat How Problem |
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219 | (7) |
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16.2 The Vibrating String Problem |
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226 | (8) |
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16.3 Functions Defined by Infinite Series |
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234 | (9) |
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16.4 Verifying the Heat Flow Problem Solution |
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243 | (6) |
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247 | (2) |
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III Classical Fourier Transforms |
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249 | (260) |
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17 Heuristic Derivation of the Classical Fourier Transform |
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251 | (6) |
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17.1 Riemann Sums over the Entire Real Line |
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251 | (2) |
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253 | (2) |
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255 | (2) |
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18 Integrals on Infinite Intervals |
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257 | (22) |
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18.1 Absolutely Integrable Functions |
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257 | (4) |
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18.2 The Set of Absolutely Integrable Functions |
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261 | (1) |
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261 | (7) |
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18.4 Functions with Two Variables |
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268 | (11) |
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276 | (3) |
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19 The Fourier Integral Transforms |
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279 | (18) |
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19.1 Definitions, Notation and Terminology |
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279 | (2) |
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281 | (2) |
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283 | (1) |
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284 | (2) |
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19.5 Other Integral Formulas (A Warning) |
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286 | (1) |
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19.6 Some Properties of the Transformed Functions |
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287 | (10) |
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294 | (3) |
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20 Classical Fourier Transforms and Classically Transformable Functions |
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297 | (22) |
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298 | (4) |
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20.2 The Set of Classically Transformable Functions |
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302 | (2) |
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20.3 The Complete Classical Fourier Transforms |
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304 | (4) |
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20.4 What Is and Is Not Classically Transformable? |
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308 | (2) |
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20.5 Finite Duration and Finite Bandwidth Functions |
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310 | (3) |
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20.6 More on Terminology, Notation and Conventions |
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313 | (6) |
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314 | (5) |
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21 Some Elementary Identities: Translation, Scaling and Conjugation |
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319 | (20) |
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319 | (8) |
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327 | (1) |
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21.3 Practical Transform Computing |
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328 | (4) |
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21.4 Complex Conjugation and Related Symmetries |
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332 | (7) |
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335 | (4) |
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22 Differentiation and Fourier Transforms |
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339 | (20) |
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22.1 The Differentiation Identities |
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339 | (7) |
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22.2 Rigorous Derivation of the Differential Identities |
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346 | (3) |
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22.3 Higher Order Differential Identities |
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349 | (2) |
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22.4 Anti-Differentiation and Integral Identities |
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351 | (8) |
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356 | (3) |
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23 Gaussians and Gaussian-Like Functions |
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359 | (16) |
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359 | (5) |
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364 | (4) |
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23.3 Gaussian-Like Functions |
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368 | (7) |
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373 | (2) |
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24 Convolution and Transforms of Products |
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375 | (24) |
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24.1 Derivation of the Convolution Formula |
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375 | (2) |
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24.2 Basic Formulas and Properties of Convolution |
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377 | (2) |
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24.3 Algebraic Properties |
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379 | (3) |
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24.4 Computing Convolutions |
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382 | (6) |
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24.5 Existence, Smoothness and Derivatives of Convolutions |
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388 | (4) |
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24.6 Convolution and Fourier Analysis |
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392 | (7) |
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395 | (4) |
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25 Correlation, Square-Integrable Functions and the Fundamental Identity |
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399 | (20) |
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399 | (4) |
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25.2 Square-Integrable/Finite Energy Functions |
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403 | (9) |
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25.3 The Fundamental Identity |
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412 | (7) |
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416 | (3) |
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26 Generalizing the Classical Theory: A Naive Approach |
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419 | (28) |
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419 | (7) |
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26.2 Transforms of Periodic Functions |
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426 | (3) |
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26.3 Arrays of Delta Functions |
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429 | (3) |
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26.4 The Generalized Derivative |
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432 | (15) |
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444 | (3) |
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27 Fourier Analysis in the Analysis of Systems |
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447 | (16) |
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27.1 Linear, Shift-Invariant Systems |
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447 | (7) |
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27.2 Computing Outputs for LSI Systems |
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454 | (9) |
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461 | (2) |
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28 Multi-Dimensional Fourier Transforms |
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463 | (8) |
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463 | (3) |
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28.2 Computing Multi-Dimensional Transforms |
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466 | (5) |
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470 | (1) |
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471 | (20) |
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29.1 An Elementary Identity Sequence |
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471 | (2) |
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29.2 General Identity Sequences |
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473 | (4) |
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29.3 Gaussian Identity Sequences |
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477 | (4) |
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29.4 Verifying Identity Sequences |
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481 | (4) |
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29.5 An Application (with Exercises) |
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485 | (2) |
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29.6 Laplace Transforms as Fourier Transforms |
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487 | (4) |
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489 | (2) |
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30 Gaussians as Test Functions and Proofs of Important Theorems |
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491 | (18) |
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30.1 Testing for Equality with Gaussians |
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491 | (1) |
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30.2 The Fundamental Theorem on Invertibility |
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492 | (3) |
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30.3 The Fourier Differential Identities |
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495 | (6) |
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30.4 The Fundamental and Convolution Identities of Fourier Analysis |
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501 | (8) |
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IV Generalized Functions and Fourier Transforms |
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509 | (198) |
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31 A Starting Point for the Generalized Theory |
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511 | (4) |
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511 | (4) |
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514 | (1) |
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32 Gaussian Test Functions |
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515 | (22) |
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32.1 The Space of Gaussian Test Functions |
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515 | (4) |
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32.2 On Using the Space of Gaussian Test Functions |
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519 | (2) |
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32.3 Other Test Function Spaces and a Confession |
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521 | (1) |
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32.4 More on Gaussian Test Functions |
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522 | (7) |
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32.5 Norms and Operational Continuity |
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529 | (8) |
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535 | (2) |
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537 | (30) |
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537 | (3) |
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33.2 Generalized Functions |
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540 | (7) |
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33.3 Basic Algebra of Generalized Functions |
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547 | (6) |
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33.4 Generalized Functions Based on Other Test Function Spaces |
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553 | (1) |
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33.5 Some Consequences of Functional Continuity |
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553 | (6) |
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33.6 The Details of Functional Continuity |
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559 | (8) |
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564 | (3) |
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34 Sequences and Series of Generalized Functions |
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567 | (20) |
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34.1 Sequences and Limits |
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567 | (7) |
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34.2 Infinite Series (Summations) |
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574 | (3) |
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34.3 A Little More on Delta Functions |
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577 | (2) |
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34.4 Arrays of Delta Functions |
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579 | (8) |
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583 | (4) |
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35 Basic Transforms of Generalized Fourier Analysis |
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587 | (42) |
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587 | (5) |
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35.2 Generalized Scaling of the Variable |
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592 | (5) |
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35.3 Generalized Translation/Shifting |
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597 | (8) |
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35.4 The Generalized Derivative |
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605 | (8) |
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35.5 Transforms of Limits and Series |
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613 | (1) |
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35.6 Adjoint-Defined Transforms in General |
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614 | (7) |
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35.7 Generalized Complex Conjugation |
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621 | (8) |
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623 | (6) |
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36 Generalized Products, Convolutions and Definite Integrals |
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629 | (20) |
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36.1 Multiplication and Convolution |
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630 | (9) |
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36.2 Definite Integrals of Generalized Functions |
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639 | (4) |
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36.3 Appendix: On Defining Generalized Products and Convolutions |
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643 | (6) |
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646 | (3) |
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37 Periodic Functions and Regular Arrays |
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649 | (24) |
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37.1 Periodic Generalized Functions |
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649 | (6) |
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37.2 Fourier Series for Periodic Generalized Functions |
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655 | (8) |
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37.3 On Proving Theorem 37.5 |
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663 | (10) |
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671 | (2) |
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38 Pole Functions and General Solutions to Simple Equations |
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673 | (34) |
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38.1 Basics on Solving Simple Algebraic Equations |
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674 | (3) |
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38.2 Homogeneous Equations with Polynomial Factors |
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677 | (12) |
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38.3 Nonhomogeneous Equations with Polynomial Factors |
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689 | (4) |
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693 | (7) |
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38.5 Pole Functions in Transforms, Products and Solutions |
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700 | (7) |
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705 | (2) |
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707 | (54) |
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39 Periodic, Regular Arrays |
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709 | (12) |
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39.1 The Index Period and Other Basic Notions |
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709 | (2) |
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39.2 Fourier Series and Transforms of Periodic, Regular Arrays |
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711 | (10) |
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720 | (1) |
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40 Sampling, Discrete Fourier Transforms and FFTs |
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721 | (40) |
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40.1 Some General Conventions and Terminology |
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721 | (1) |
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40.2 Sampling and the Discrete Approximation |
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722 | (3) |
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40.3 The Discrete Approximation and Its Transforms |
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725 | (12) |
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40.4 The Discrete Fourier Transforms |
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737 | (4) |
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40.5 Discrete Transform Identities |
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741 | (6) |
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40.6 Fast Fourier Transforms |
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747 | (14) |
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756 | (5) |
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Tables, References and Answers |
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761 | (22) |
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Table A.1 Fourier Transforms of Some Common Functions |
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763 | (4) |
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Table A.2 Identities for the Fourier Transforms |
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767 | (2) |
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769 | (2) |
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Answers to Selected Exercises |
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771 | (12) |
Index |
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