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34 lines
1.3 KiB
Zig
34 lines
1.3 KiB
Zig
2 years ago
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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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// seen in the last exercise, it naturally offers itself to use the
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// very large variety of C functions for the own programs.
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// In addition immediately 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 angel. Let's go.
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const std = @import("std");
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const c = @cImport({
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// What do wee need here?
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???
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});
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pub fn main() !void {
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const angel = 765.2;
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const circle = 360;
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// Here we call the C function 'fmod' to get our normalized angel.
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const result = c.fmod(angel, circle);
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std.debug.print("The normalized angle of {d: >3.1} degrees is {d: >3.1} degrees.\n", .{ angel, result });
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}
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