Reading in data from file in certain format

This is a discussion on Reading in data from file in certain format within the C Programming forums, part of the General Programming Boards category; I have two text files containing the complex values of some function: f[0, 6] = 0.00006639570. - 6.00456*I; f[1, 6] ...

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    Reading in data from file in certain format

    I have two text files containing the complex values of some function:
    f[0, 6] = 0.00006639570. - 6.00456*I; f[1, 6] = 0.00003602 +0.0039842775.*I; f[0, 7] = 0.0000663- 6.00383226386*I; f[1, 7] = 60233709 + 0.00039842*I; . . . and similary another with g[x,y].

    I would like my code to perform a loop that reads in the data from these files into a list of vectors of complex numbers that I can then utilise, can this be done?

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    Quote Originally Posted by fpghost View Post
    I have two text files containing the complex values of some function:
    f[0, 6] = 0.00006639570. - 6.00456*I; f[1, 6] = 0.00003602 +0.0039842775.*I; f[0, 7] = 0.0000663- 6.00383226386*I; f[1, 7] = 60233709 + 0.00039842*I; . . . and similary another with g[x,y].

    I would like my code to perform a loop that reads in the data from these files into a list of vectors of complex numbers that I can then utilise, can this be done?
    Welcome to the forum, fpghost!

    This is C, we do everything we can imagine, damn near!

    Looks to me like you want to read in some floating point numbers from a file, into an array[] of doubles.

    Why not run through a bit of the C tutorial (link is in the C Tutorial tab at the top of the forum), and get familiar with some C basics.

    Then get started, and post back if and when you have a problem. We are a bit of indentation nuts, so please, use [code] tags around your code and indent just as if you were totally sane, even though that may not otherwise be proven.

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    Quote Originally Posted by Adak View Post
    Welcome to the forum, fpghost!

    This is C, we do everything we can imagine, damn near!

    Looks to me like you want to read in some floating point numbers from a file, into an array[] of doubles.

    Why not run through a bit of the C tutorial (link is in the C Tutorial tab at the top of the forum), and get familiar with some C basics.

    Then get started, and post back if and when you have a problem. We are a bit of indentation nuts, so please, use [code] tags around your code and indent just as if you were totally sane, even though that may not otherwise be proven.
    Hi, thanks, I will try and use the code tags in future.

    I know I can use cin to read in the data. The problem is the data list is of variable length and is also in a tricky format (see OP), so I'm guessing some kind of vector might be best. I really need to be able to then access it for any given parameters, e.g. schematically: f[1,2] and get back the correct complex number, say "1.25+9.87i". Hence I was thinking some kind of vector of complex type container, but was hoping someone could help with the details..

    It is possible I could change this input format slightly, but nevertheless it boils down to me having complex numbers indexed by two parameters (x,y); I need to read them in and then be able to access the complex number for a given point in the parameter space.

    Maybe I need some kind of HashTable?
    Last edited by fpghost; 11-22-2012 at 10:02 AM.

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    I would use a struct (a record), with the struct members being these other parts you need to save and reference during your searches. Typically, we use fixed length arrays (although the very latest standard for C adds variable length arrays), make them a bit oversized and in the rare case that isn't enough, we reallocate the array to a larger size with realloc() (defined in the stdlib.h include file).

    If you are using cin however, that is C++, and they have container that automatically alter their size. Perhaps you were looking for the C++ forum?

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    Quote Originally Posted by Adak View Post
    I would use a struct (a record), with the struct members being these other parts you need to save and reference during your searches. Typically, we use fixed length arrays (although the very latest standard for C adds variable length arrays), make them a bit oversized and in the rare case that isn't enough, we reallocate the array to a larger size with realloc() (defined in the stdlib.h include file).

    If you are using cin however, that is C++, and they have container that automatically alter their size. Perhaps you were looking for the C++ forum?
    AH yes, sorry I was looking for C++ forum. Is it possible to move my thread there? or I can repost it?

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    I'd just repost it. It's a slow day being Thanksgiving and all.

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