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Full Discussion: finding the nth match
Top Forums UNIX for Dummies Questions & Answers finding the nth match Post 302530984 by Corona688 on Wednesday 15th of June 2011 02:16:58 PM
Old 06-15-2011
Quote:
Originally Posted by countryStyle
See....you did not need data to answer and there was no problem adding on the excellent commentary/lead about awk.
If I lucked out into something that did exactly what you wanted the very first try, then I lucked out. Getting people to explain what they really want can be as difficult as -- well -- as difficult as getting you to post your data.

Simple questions shouldn't always be taken at face value, either
Quote:
Originally Posted by qdb.us
<glyph> For example - if you came in here asking "how do I use a jackhammer" we might ask "why do you need to use a jackhammer"
<glyph> If the answer to the latter question is "to knock my grandmother's head off to let out the evil spirits that gave her cancer", then maybe the problem is actually unrelated to jackhammers
So frequent posters here develop some habitual questions. 1) Post your OS (thank you for that), 2) Post your data! It makes things a lot smoother all around.

Quote:
I know a lot of people often ask for the answer to their specific issue and want YOU the other poster to do all the work for them (sometimes very practical). I am still at the general question looking to get more of a clue phase but if you want to do all my work for me let me know...I am certain you can do it fast.
You know the saying, a bird in the hand is worth two in the bush? It doesn't have to be either/or. I can make a simple example that works with your data without doing all your work for you, which will look more straighforward than one for random data I had lying around.
Quote:
I am not working with large files here and performance is not an issue...... The line is easy to use and works in the Bash shell so....why is this a silly solution, performance, crossplatform issues?
Running one program instead of two is much better, and if you can avoid any programs, that's better yet! External programs take time to start and stop, even for tiny files -- especially for tiny files, where most of the time would be spent loading/quitting instead of work. And pipes can waste time communicating with each other (grep reads, writes, tail reads, writes, head reads, writes.) Both of these can add up faster than you'd expect. One of my first shell programming experiments was a text linewrapper that ran at the blazing speed of one kilobyte per second.

This is also why I'm curious what your program actually is and how you're using this 'get line x' code, because if grep | tail | head is your way of loading individual lines of data from file, you might want to ask about better ways to organize your program.
 

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LEARN ABOUT DEBIAN

quiz

QUIZ(6) 							 BSD Games Manual							   QUIZ(6)

NAME

     quiz -- random knowledge tests

SYNOPSIS

     quiz [-t] [-i file] [question answer]

DESCRIPTION

     The quiz utility tests your knowledge of random facts.  It has a database of subjects from which you can choose.  With no arguments, quiz
     displays the list of available subjects.

     The options are as follows:

     -t      Use tutorial mode, in which questions are repeated later if you didn't get them right the first time, and new questions are presented
	     less frequently to help you learn the older ones.

     -i      Specify an alternative index file.

     Subjects are divided into categories.  You can pick any two categories from the same subject.  quiz will ask questions from the first cate-
     gory and it expects answers from the second category.  For example, the command ``quiz victim killer'' asks questions which are the names of
     victims, and expects you to answer with the cause of their untimely demise, whereas the command ``quiz killer victim'' works the other way
     around.

     If you get the answer wrong, quiz lets you try again.  To see the right answer, enter a blank line.

   Index and Data File Syntax
     The index and data files have a similar syntax.  Lines in them consist of several categories separated by colons.	The categories are regular
     expressions formed using the following meta-characters:

	   pat|pat  alternative patterns
	   {pat}    optional pattern
	   [pat]    delimiters, as in pat[pat|pat]pat

     In an index file, each line represents a subject.	The first category in each subject is the pathname of the data file for the subject.  The
     remaining categories are regular expressions for the titles of each category in the subject.

     In data files, each line represents a question/answer set.  Each category is the information for the question/answer for that category.

     The backslash character (``'') is used to quote syntactically significant characters, or at the end of a line to signify that a continuation
     line follows.

     If either a question or its answer is empty, quiz will refrain from asking it.

FILES

     /usr/share/games/bsdgames/quiz  The default index and data files.

BUGS

     quiz is pretty cynical about certain subjects.

BSD
								   May 31, 1993 							       BSD
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