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@ -1,19 +1,26 @@
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//
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// Often, C functions are used where no equivalent Zig function exists
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// yet. Since the integration of a C function is very simple, as already
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// yet. Okay, that's getting less and less. ;-)
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//
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// Since the integration of a C function is very simple, as already
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// seen in the last exercise, it naturally offers itself to use the
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// very large variety of C functions for our own programs.
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// As an example:
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//
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// Let's say we have a given angle of 765.2 degrees. If we want to
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// normalize that, it means that we have to subtract X * 360 degrees
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// to get the correct angle. How could we do that? A good method is
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// to use the modulo function. But if we write "765.2 % 360", it won't
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// work, because the standard modulo function works only with integer
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// values. In the C library "math", there is a function called "fmod";
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// the "f" stands for floating and means that we can solve modulo for
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// real numbers. With this function, it should be possible to normalize
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// our angle. Let's go.
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// to get the correct angle.
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// How could we do that? A good method is to use the modulo function.
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// But if we write "765.2 % 360", it only works with float values
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// that are known at compile time.
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// In Zig, we would use %mod(a, b) instead.
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//
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// Let us now assume that we cannot do this in Zig, but only with
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// a C function from the standard library. In the library "math",
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// there is a function called "fmod"; the "f" stands for floating
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// and means that we can solve modulo for real numbers. With this
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// function, it should be possible to normalize our angle.
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// Let's go.
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const std = @import("std");
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