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Comments:
<0> i.e. that's what it was designed to do....read a line
<1> http://www.cplusplus.com/doc/tutorial/files.html
<2> hmmm but each line contains two values :)
<1> there's an example in the middle of that page
<0> and???
<1> a line is ended by an end of line character not whitespace
<3> is this pharagraph easy to understand?
<3> Subcl***es retain their overridden methods when referred to by supercl*** pointers
<3> or references. They lose their uniqueness when cast to a supercl*** object. The loss
<3> of overridden methods and subcl*** data is called slicing.
<4> calc !tutorial
<5> !tutorial = C++ is not the sort of thing you learn (well) from a bunch of second-rate tutorials on the Web. The preferred method is to buy a good book (e.g. Koenig & Moo's "Accelerated C++"), get a good C++ compiler or development environment (e.g. Dev-C++), and practice a lot. You could even take a course at your local community college.
<4> beginner_: that's pretty easy, IMHO.
<0> beginner_ I think it's written poorly
<0> I've never liked the idea of supercl*** and subcl***
<4> It's probably a bit too compact for a beginner. (e.g. the name "slicing" is non-obvious to the beginner)
<2> vawjr if I use getline aren't I going to get one line of a text file
<1> yes, thats what you want isnt it?
<2> no I have a file that has
<2> f 0939 \n m 5852 \n f 9659 ...
<3> so actualy it means?
<0> SJr|nx__ yes, of course.... but if you KNOW there are two values on each line, then lines aren't all that ijportant
<2> the \n are actually new lines
<2> vawjr yeah this is a beginning c++ course
<2> I know on each line there is a gender and a GPA
<1> yes, getline will read f 0939 then return
<2> right but then I'd have to manually parse that
<2> as opposed to
<2> inData >> gender >> gpa;
<0> so.... while(instream >> gender >> gpa) {/* do your calculations */}
<2> oh
<2> hmmmm
<2> okay
<0> so put the inData >> gender >> gpa
<0> inside a while
<2> as the conditional
<0> yeah
<2> wow
<2> I hate doing that
<0> forget about the peek nonsense
<2> but I should learn :P
<0> WHY?
<0> why would you hate doing that?
<3> lol look what it says, =)
<2> I'm too much of a newb
<2> just like I hate doing
<0> no
<2> ! something I prefer == FALSE
<0> you've been using poor langages
<2> lol no you can do that in PHP too
<2> and yes probably :)
<3> the book says that defining all the functions virtualy is a good idea as a summary
<2> you do that with MySQL in PHP
<2> and it seems sorta wierd to me
<2> I guess I should become more familiar with it.
<0> well, do you know the "value" of the expression "inData >> gender >> gpa" ?
<2> I ***ume that if the extractions are successful its true, but if they fail then the while loop will break.
<0> nope
<2> then?
<0> the "value" is "inData"
<2> then?ah
<2> ah
<2> and if its EOF
<0> operator >> returns a reference to the stream
<2> then its false
<2> ?
<0> it will never be EOF
<2> hmmmm
<0> it's the STREAM
<2> okay so when does the loop actually break?
<0> if(somestream) will be true ONLY if the stream is "good()"
<2> good() ?
<0> somestream.good()
<0> not fail()
<0> not bad()
<2> oh neat
<0> nol eof()
<2> somestream.good() = true?
<0> ****
<0> no
<2> lol
<2> I'm coming to #math for some vector Calculus in about 40 minutes :P
<0> .good() doesn't return something you can ***ign to
<2> oh
<2> no
<2> sorry
<6> 'morning ;)
<2> that was sloppy
<2> I just meant somestream.good() will return true
<0> indeed
<2> is that correct?
<0> if nothing is wrong, yes..but very seldom do you see anyone call it explicitly
<2> but if there is no more data in the ifstream, then .good() will return false?
<0> no
<1> if eof(), fail() or bad() return true then good() returns false otherwise it returns true
<0> I told you you wrtie whle (inData >> gender >> gpa)
<2> I did
<2> write that
<0> then why are you worrying about good() ?
<2> Hmmmmm
<2> for the same reason I don't just e-mail you the ***ignment and get you to do it for me
<2> however
<2> my Vector Calc
<0> I wouldn't have done it anyway
<2> lol
<2> well thats why I am asking
<7> anybody knows where to get codeview??
<8> comtria!
<2> If I have a string declared with string FILENAME = "file.txt";
<2> how can I use that to open a file
<2> inData.open(FILENAME);
<2> errors out.
<2> ques4.cpp:26: error: no matching function for call to 'std::basic_ifstream<char, std::char_traits<char> >::open(std::string&)' /usr/lib/gcc/i486-linux-gnu/4.0.3/../../../../include/c++/4.0.3/fstream:495: note: candidates are: void std::basic_ifstream<_CharT, _Traits>::open(const char*, std::_Ios_Openmode) [with _CharT = char, _Traits = std::char_traits<char>]
<9> there is no constructor for std::string
<9> inData.open(FILENAME.c_str());
<0> cn28h yes, interesting oversight on the part of the committee
<2> ah cool thanks
<0> and why the hell you using all caps for FILENAME
<2> because its a const
<0> 1) you didn't show it that way
<0> and who cares that it's const ?
<2> 1) that wasn't relevant to the problem
<2> 2) my teacher does cause we have a notation to follow
<2> constants are all capitals
<0> then write it as ****ing const
<0> and youre teacher should be shot
<2> I did write it as const
<2> const string FILENAME = "file.txt";
<0> you SAID declared with string FILENAME = "file.txt";
<0> that isn't const, I'm sorry
<2> as I said the fact that it was constant wasn't relevant at the time, so I dropped it.
<9> I thought the all caps was for macros
<2> oh
<2> hmmmm nope
<2> its not my prefered choice of Variable naming but its what we use in the course
<0> well, it's an interesting, if misguieded convention
<2> constants being all capitals and words seperated by _ is wierd?
<0> yes, because constants have a habit if becoming not
<0> like when you extend the program to have the user enter the filename
<0> or write a loop to process several files
<2> well
<2> thats our syntax
<2> and I'm not about to argue with my professor
<2> well not Syntax, sorry convention
<0> tsk tsk
<0> your professor isn't right all the time you know
<2> I'd argue with my VB professor, but I think this guy knows what he is talking about.
<2> Right but again this isn't a factual arguement. Its a matter of convention, and as the authoritive body for our cl*** he can define the convention we use, and there is no logical basis to dispute that with.
<0> you can point out that constants have a habit of migrating to not
<0> then the convention (if beleived) leads to lies
<2> I could but one, that would certainly never happen in any of our programs in the cl***. Secondly if he retorts with absolutetly anything I have no where to go from there. Thirdly its argueable that its only poor planning that would result in a change.
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