Showing Revision 3 created 05/24/2016 by Udacity Robot.

1. タイトル：
   Overview of Course - Software Debugging
2. 概説：

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   My name is Andreas Zeller. I'm a researcher at Saarland University in Germany.
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   And I am researching large programs and why they fail.
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   I have done some fail work in automatic debugging, also in mining the histories of programs.
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   I've been working with companies such as Microsoft, SAP, or Google,
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   examined their bugs, finding out what was wrong, and it struck me
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   that there's almost no teaching material available on debugging and how to debug programs.
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   So today, I'm going start with you a course on how to do debugging systematically,
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    effectively, and in many cases, even automatically--enjoy.
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    Welcome to the Udacity course on debugging.
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    The aim of this course is to teach a systematic approach to debugging
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    and we're even going to explore a number of automatic tools that do the debugging for you.
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    We're going to explore how debuggers work.
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    In particular, the scientific method of debugging by which
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    through a series of experiments we gradually refine a hypothesis
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    until we end up with a diagnosis on why the program failed.
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    On top of that, we're going to build our own interactive debugger in Python.
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    In the next unit, I'm going to introduce you to one of the most
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    powerful debugging tools ever invented, that is assertions.
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    Assertions are statements in the program that automatically check
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    whether the state of the program is still correct.
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    That is, while you're program is executing, the computer constantly monitors
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    the program on whether a bug has occurred.
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    This allows you to very quickly and effectively find out where a bug was first introduced.
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    On top of that, we're going to build a tool that makes you infer assertions from executions.
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    In unit 3, I'm going to show you a technique named delta debugging
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    which automatically simplifies problems.
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    For instance, here's this 900-line HTML file which causes to crash in a program which processes it.
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    With delta debugging, you can reduce this to just the eight characters
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    that produce the bug just as well and all of this automatically.
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    In the next unit, I'm going to show you how to find out where a specific failure came from.
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    You see an execution as a series of states.
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    We are going to explore techniques that help you in tracking
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    the way of an error all through the program execution.
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    And on top of that, we're going to build a tool that isolates such cause effect chamge automatically.
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    In unit 5, we've been looking at reproducing failures.
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    We're going to look at all the various input sources for your program
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    and discuss how to capture and replay them such that you can faithfully
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    reproduce a failure that happens in the field.
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    Plus, we're going to explore statistical debugging which collects data from the field
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    to tell you which parts of your program are most likely to be related to the failure.
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    In unit 6, we're going to see how to mine information
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    from bug data bases and change data bases in order to figure out
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    where bugs have been in your program in the past, where they accumulate,
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    and which parts of your program therefore are going to be the most back prone in the future.
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    And again this is a fully automatic technique.
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    This is so far, you've had no fun in debugging because it just sucks the life out of you.
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    The aim of this course is to get most of the debugging effort off your shoulders
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    because you can have the computer take care of most of the debugging work.
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    So your mind is free for doing something more creative than debugging.