"M_PI_2": repeat-defined macros

Problems CAUTION: "M_PI_2": repeat-defined macros

Analysis: We can use the macro definition math.h library on Visual Studio conflict with other libraries math library by adding "_USE_MATH_DEFINES" to eliminate math.h defined macros.

#if defined _USE_MATH_DEFINES && !defined _MATH_DEFINES_DEFINED
    #define _MATH_DEFINES_DEFINED
    // Definitions of useful mathematical constants
    //
    // Define _USE_MATH_DEFINES before including <math.h> to expose these macro
    // definitions for common math constants.  These are placed under an #ifdef
    // since these commonly-defined names are not part of the C or C++ standards
    #define M_E        2.71828182845904523536   // e
    #define M_LOG2E    1.44269504088896340736   // log2(e)
    #define M_LOG10E   0.434294481903251827651  // log10(e)
    #define M_LN2      0.693147180559945309417  // ln(2)
    #define M_LN10     2.30258509299404568402   // ln(10)
    #define M_PI       3.14159265358979323846   // pi
    #define M_PI_2     1.57079632679489661923   // pi/2
    #define M_PI_4     0.785398163397448309616  // pi/4
    #define M_1_PI     0.318309886183790671538  // 1/pi
    #define M_2_PI     0.636619772367581343076  // 2/pi
    #define M_2_SQRTPI 1.12837916709551257390   // 2/sqrt(pi)
    #define M_SQRT2    1.41421356237309504880   // sqrt(2)
    #define M_SQRT1_2  0.707106781186547524401  // 1/sqrt(2)
#endif

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Solution:

Need to "project", right-click, select "Properties", then "Preprocessor definitions" in the "C / C ++" in the "pre-processor" configuration group added "_USE_MATH_DEFINES".

    2) Add the appropriate header file  #define _USE_MATH_DEFINES