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 Summary ```#include <80C517.h> float tan517 ( float x); /* value to calculate tangent of */ ``` Description The tan517 function calculates the tangent of the floating-point value x. Note This routine uses the arithmetic unit of the Infineon C517x/C509 to provide accelerated execution speed. Do not use this routine with a CPU that does not support this feature. Return Value The tan517 function returns the tangent of x. The value of x must be in the range ±2^32 (±4294967296.0). Outside this value range an NaN error is returned. For x = c (±π/2;), {c = (2k+1); k ∈ N}, tan517 returns ±INF. See Also Example ```#include <80C517.h> #include /* for printf */ void tst_tan517 (void) { float x; float y; float pi; pi = 3.14159265; for (x = -(pi/4); x < (pi/4); x += 0.1) { y = tan517 (x); printf ("TAN517(%f) = %f\n", x, y); } } ```

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