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| 22 | <title>Mixed Mode (GNU C Language Manual)</title>
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| 30 | <link href="Symbol-Index.html" rel="index" title="Symbol Index">
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| 31 | <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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| 32 | <link href="Arithmetic.html" rel="up" title="Arithmetic">
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| 33 | <link href="Division-and-Remainder.html" rel="next" title="Division and Remainder">
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| 57 | <body lang="en">
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| 58 | <span id="Mixed-Mode"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Division-and-Remainder.html" accesskey="n" rel="next">Division and Remainder</a>, Previous: <a href="Integer-Overflow.html" accesskey="p" rel="prev">Integer Overflow</a>, Up: <a href="Arithmetic.html" accesskey="u" rel="up">Arithmetic</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Index.html" title="Index" rel="index">Index</a>]</p>
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| 61 | </div>
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| 62 | <hr>
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| 63 | <span id="Mixed_002dMode-Arithmetic"></span><h3 class="section">6.4 Mixed-Mode Arithmetic</h3>
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| 64 |
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| 65 | <p>Mixing integers and floating-point numbers in a basic arithmetic
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| 66 | operation converts the integers automatically to floating point.
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| 67 | In most cases, this gives exactly the desired results.
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| 68 | But sometimes it matters precisely where the conversion occurs.
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| 69 | </p>
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| 70 | <p>If <code>i</code> and <code>j</code> are integers, <code>(i + j) * 2.0</code> adds them
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| 71 | as an integer, then converts the sum to floating point for the
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| 72 | multiplication. If the addition gets an overflow, that is not
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| 73 | equivalent to converting both integers to floating point and then
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| 74 | adding them. You can get the latter result by explicitly converting
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| 75 | the integers, as in <code>((double) i + (double) j) * 2.0</code>.
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| 76 | See <a href="Explicit-Type-Conversion.html">Explicit Type Conversion</a>.
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| 77 | </p>
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| 78 | <p>Adding or multiplying several values, including some integers and some
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| 79 | floating point, does the operations left to right. Thus, <code>3.0 +
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| 80 | i + j</code> converts <code>i</code> to floating point, then adds 3.0, then
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| 81 | converts <code>j</code> to floating point and adds that. You can specify a
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| 82 | different order using parentheses: <code>3.0 + (i + j)</code> adds <code>i</code>
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| 83 | and <code>j</code> first and then adds that result (converting to floating
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| 84 | point) to 3.0. In this respect, C differs from other languages, such
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| 85 | as Fortran.
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| 86 | </p>
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| 87 |
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| 88 |
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| 89 |
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| 90 | </body>
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| 91 | </html>
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