import re
regex = re.compile(r"(1\.\d+)\D+?(?:(\S+)\s+)+?(\d+)", flags=re.MULTILINE | re.IGNORECASE)
test_str = (" BRIEF CONTENTS\n"
" Chapter1 Basic Concepts 1\n"
" Chapter2 Resistive Circuits 24\n"
" Chapter3 Nodal and Loop Analysis Techniques 89\n"
" Chapter4 Operational Amplifiers 147\n"
" Chapter5 Additional Analysis Techniques 171\n"
" Chapter6 Capacitance and Inductance 219\n"
" Chapter7 First- and Second-Order Transient Circuits 252\n"
" Chapter8 AC Steady-State Analysis 305\n"
" Chapter9 Steady-State Power Analysis 362\n"
" Chapter10 Magnetically Coupled Networks 411\n"
" Chapter11 Polyphase Circuits 450\n"
" Chapter12 Variable-Frequency Network Performance 482\n"
" Chapter13 The Laplace Transform 543\n"
" Chapter14 Application of the Laplace Transform to \n"
" Circuit Analysis 569\n"
" Chapter15 Fourier Analysis Techniques 617\n"
" Appendix Complex Numbers 659\n"
" vi\n"
" FM.indd viFM.indd vi 21/11/14 11:11 AM21/11/14 11:11 AM\n"
" CONTENTS\n"
" Preface ix 5.3 Thévenin’s and Norton’s Theorems 179\n"
" Chapterone 5.4 Maximum Power Transfer 197\n"
" Summary 202\n"
" Basic Concepts 1 Problems 202\n"
" 1.1 System of Units 2 Chaptersix \n"
" 1.2 Basic Quantities 2 Capacitance and Inductance 219\n"
" 1.3 Circuit Elements 8\n"
" Summary 17 6.1 Capacitors 220\n"
" Problems 18 6.2 Inductors 227\n"
" 6.3 Capacitor and Inductor Combinations 236\n"
" Chaptertwo Summary 241\n"
" Resistive Circuits 24 Problems 241\n"
" 2.1 Ohm’s Law 25 Chapterseven \n"
" 2.2 Kirchhoff’s Laws 30 First- and Second-Order Transient Circuits 252\n"
" 2.3 Single-Loop Circuits 38\n"
" 2.4 Single-Node-Pair Circuits 45 7.1 Introduction 253\n"
" 2.5 Series and Parallel Resistor Combinations 50 7.2 First-Order Circuits 254\n"
" 2.6 Wye Delta Transformations 59 7.3 Second-Order Circuits 275\n"
" 2.7 Circuits with Dependent Sources 63 Summary 289\n"
" Summary 68 Problems 289\n"
" Problems 69 Chaptereight \n"
" Chapterthree AC Steady-State Analysis 305\n"
" Nodal and Loop Analysis Techniques 89 8.1 Sinusoids 306\n"
" 3.1 Nodal Analysis 90 8.2 Sinusoidal and Complex Forcing Functions 309\n"
" 3.2 Loop Analysis 111 8.3 Phasors 312\n"
" Summary 128 8.4 Phasor Relationships for Circuit Elements 314\n"
" Problems 129 8.5 Impedance and Admittance 318\n"
" 8.6 Phasor Diagrams 325\n"
" Chapterfour 8.7 Basic Analysis Using Kirchhoff’s Laws 328\n"
" Operational Amplifiers 147 8.8 Analysis Techniques 331\n"
" Summary 344\n"
" 4.1 Introduction 148 Problems 344\n"
" 4.2 Op-Amp Models 148\n"
" 4.3 Fundamental Op-Amp Circuits 154 Chapternine \n"
" Summary 163 Steady-State Power Analysis 362\n"
" Problems 163 9.1 Instantaneous Power 363\n"
" Chapterfi ve 9.2 Average Power 364\n"
" Additional Analysis Techniques 171 9.3 Maximum Average Power Transfer 369\n"
" 9.4 Effective or rms Values 374\n"
" 5.1 Introduction 172 9.5 The Power Factor 377\n"
" 5.2 Superposition 174 9.6 Complex Power 379\n"
" vii\n"
" FM.indd viiFM.indd vii 21/11/14 11:11 AM21/11/14 11:11 AM\n"
" viii CONTENTS\n"
" 9.7 Power Factor Correction 384 13.3 Transform Pairs 547\n"
" 9.8 Single-Phase Three-Wire Circuits 388 13.4 Properties of the Transform 549\n"
" 9.9 Safety Considerations 391 13.5 Performing the Inverse Transform 551\n"
" Summary 399 13.6 Convolution Integral 557\n"
" Problems 399 13.7 Initial-Value and Final-Value Theorems 560\n"
" 13.8 Solving Differential Equations with Laplace \n"
" Chapterten Transforms 562\n"
" Magnetically Coupled Networks 411 Summary 564\n"
" 10.1 Mutual Inductance 412 Problems 564\n"
" 10.2 Energy Analysis 423 Chapterfourteen \n"
" 10.3 The Ideal Transformer 426 Application of the Laplace Transform to \n"
" 10.4 Safety Considerations 436 Circuit Analysis 569\n"
" Summary 437\n"
" Problems 438 14.1 Laplace Circuit Solutions 570\n"
" 14.2 Circuit Element Models 571\n"
" Chaptereleven 14.3 Analysis Techniques 573\n"
" Polyphase Circuits 450 14.4 Transfer Function 586\n"
" 11.1 Three-Phase Circuits 451 14.5 Steady-State Response 603\n"
" 11.2 Three-Phase Connections 456 Summary 606\n"
" 11.3 Source/Load Connections 457 Problems 606\n"
" 11.4 Power Relationships 466 Chapterfi fteen \n"
" 11.5 Power Factor Correction 471 Fourier Analysis Techniques 617\n"
" Summary 475\n"
" Problems 475 15.1 Fourier Series 618\n"
" 15.2 Fourier Transform 641\n"
" Chaptertwelve Summary 651\n"
" Variable-Frequency Network Performance 482 Problems 651\n"
" 12.1 Variable Frequency-Response Analysis 483\n"
" 12.2 Sinusoidal Frequency Analysis 491 Appendix\n"
" 12.3 Resonant Circuits 500 Complex Numbers 659\n"
" 12.4 Scaling 521\n"
" 12.5 Filter Networks 523 Index 666\n"
" Summary 534\n"
" Problems 535\n"
" Chapterthirteen \n"
" The Laplace Transform 543\n"
" 13.1 Definition 544\n"
" 13.2 Two Important Singularity Functions 544\n"
" FM.indd viiiFM.indd viii 21/11/14 11:11 AM21/11/14 11:11 AM")
matches = regex.finditer(test_str)
for match_num, match in enumerate(matches, start=1):
print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}")
for group_num, group in enumerate(match.groups(), start=1):
print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html