Thread: ? about C arrays

  1. #1
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    ? about C arrays

    Hello,

    I've been searching the code for the definition of the bond_cashflow array, a class array:

    bond_cashflow

    but havn't been able to find a specific array creation statement, ie something like:

    BondCash[] bond_cashflow

    but only see this statement:

    amt_flow = new bond_cashflow [1];

    ? does the statement above automagically create the "bond_cashflow" array?

    thanks very much for any insights!
    bobK

  2. #2
    Lurking whiteflags's Avatar
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    Well in order for this to be valid C++:

    bond_cashflow * amt_cashflow;
    amt_cashflow = new bond_cashflow [1];

    bond_cashflow would need to be a type and the result would be an array called "amt_cashflow".

    Now why have you created an array of one element?

  3. #3
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    Yes that is the way that:

    amt_flow

    is defined

    Bond_cashflow * amt_flow;

    So by making "amt_flow" a pointer to a "Bond_cashflow" class, it allows one to treat the Bond_cashflow class as if it were a member of an array?

    bk

  4. #4
    C++ Witch laserlight's Avatar
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    With the mention of class and new, I believe that this question has to do with C++, not C.

    Moved to C++ forum.
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  5. #5
    Lurking whiteflags's Avatar
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    Well what are you really doing? The appropriate time for new[] (or malloc in C--I'm still not sure what language you're using) is when you need to allocate a resource, like an array of a certain type. Any other use for new[] is wrong.

  6. #6
    and the Hat of Guessing tabstop's Avatar
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    Quote Originally Posted by bobk544 View Post
    Yes that is the way that:

    amt_flow

    is defined

    Bond_cashflow * amt_flow;

    So by making "amt_flow" a pointer to a "Bond_cashflow" class, it allows one to treat the Bond_cashflow class as if it were a member of an array?

    bk
    Um ... I think you have that backwards. You're not treating the class as though you it is part of an array, you're making a whole new thing, and that thing turns out to be an array of Bond_cashflows. It doesn't change what a Bond_cashflow is itself.

  7. #7
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    ok thanks all i'm going to look at this some more and try to create a small protype, appreciate the very considerate help!

    bk

  8. #8
    Frequently Quite Prolix dwks's Avatar
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    Code:
    BondCash[] bond_cashflow
    If you're just looking for ordinary array-declaration syntax, it looks like this:
    Code:
    type array_name[size];
    In your case, that would be:
    Code:
    BondCash bond_cashflow[SIZE];
    dwk

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