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Cx51 User's Guide

Cx51 Introduction Compiling Programs Language Extensions Preprocessor Advanced Programming 8051 Derivatives Error Messages Library Reference Library Files Source Code Standard Types jmp_buf size_t va_list wchar_t Macros CBYTE CWORD DBYTE DWORD FARRAY FCARRAY FCVAR FVAR PBYTE PWORD XBYTE XWORD Routines By Category Buffer Manipulation Routines Character Routines Data Conversion Routines Intrinsic Routines Math Routines Memory Allocation Routines Stream I/O Routines String Routines Variable Length Argument Routines Miscellaneous Routines Include Files SFR Definitions 80c517.h absacc.h assert.h ctype.h float.h intrins.h limits.h math.h rtx51tny.h setjmp.h stdarg.h stddef.h stdio.h stdlib.h string.h Reference _chkfloat_ _crol_ _cror_ _getkey _irol_ _iror_ _lrol_ _lror_ _nop_ _pop_ _push_ _testbit_ _tolower _toupper abs acos acos517 asin asin517 assert atan atan2 atan517 atof atof517 atoi atol cabs calloc ceil cos cos517 cosh exp exp517 fabs floor fmod free getchar gets init_mempool isalnum isalpha iscntrl isdigit isgraph islower isprint ispunct isspace isupper isxdigit labs log log10 log10517 log517 longjmp malloc memccpy memchr memcmp memcpy memmove memset modf offsetof pow printf printf517 putchar puts rand realloc scanf scanf517 setjmp sin sin517 sinh sprintf sprintf517 sqrt sqrt517 srand sscanf sscanf517 strcat strchr strcmp strcpy strcspn strlen strncat strncmp strncpy strpbrk strpos strrchr strrpbrk strrpos strspn strstr strtod strtod517 strtok strtol strtoul switchbank tan tan517 tanh toascii toint tolower toupper ungetchar va_arg va_end va_start vprintf vsprintf Appendix

float.h

The float.h include file defines manifest constants that represent implementation-defined properties of floating-point numbers.

Defined Constant Description
DBL_DIG The precision in decimal digits for type double.
DBL_EPSILON The smallest n of type double such that 1.0 + n != 1.0.
DBL_MANT_DIG The number of mantissa digits, base DBL_RADIX, for type double.
DBL_MAX The largest finite representable value of type double.
DBL_MAX_10_EXP The maximum integer n, such that 10n is a finite representable value of type double.
DBL_MAX_EXP The maximum integer n, such that DBL_RADIXn-1 is a finite representable value of type double.
DBL_MIN The smallest normalized, finite representable value of type double.
DBL_MIN_10_EXP The minimum integer n such that 10n is a normalized, finite representable value of type double.
DBL_MIN_EXP The minimum integer n such that DBL_RADIXn-1 is a normalized, finite representable value of type double.
DBL_RADIX The radix of all double types.
DBL_ROUNDS A value that describes the current rounding mode for double operations.
  • -1 if the mode is indeterminate,
  • 0 if rounding is toward zero (this is the default for the Cx51 Compiler),
  • 1 if rounding is to nearest representable value,
  • 2 if rounding is toward +infinity,
  • 3 if rounding is toward -infinity.
FLT_DIG The precision in decimal digits for type float.
FLT_EPSILON The smallest n of type float such that 1.0 + n != 1.0.
FLT_MANT_DIG The number of mantissa digits, base FLT_RADIX, for type float.
FLT_MAX The largest finite representable value of type float.
FLT_MAX_10_EXP The maximum integer n, such that 10n is a finite representable value of type float.
FLT_MAX_EXP The maximum integer n, such that FLT_RADIXn-1 is a finite representable value of type float.
FLT_MIN The smallest normalized, finite representable value of type float.
FLT_MIN_10_EXP The minimum integer n, such that 10n is a normalized, finite representable value of type float.
FLT_MIN_EXP The minimum integer n, such that FLT_RADIXn-1 is a normalized, finite representable value of type float.
FLT_RADIX The radix of all float types.
FLT_ROUNDS A value that describes the current rounding mode for float operations.
  • -1 if the mode is indeterminate,
  • 0 if rounding is toward zero (this is the default for the Cx51 Compiler),
  • 1 if rounding is to nearest representable value,
  • 2 if rounding is toward +infinity,
  • 3 if rounding is toward -infinity.
LDBL_DIG The precision in decimal digits for type long double.
LDBL_EPSILON The smallest n of type long double such that 1.0 + n != 1.0.
LDBL_MANT_DIG The number of mantissa digits, base LDBL_RADIX, for type long double.
LDBL_MAX The largest finite representable value of type long double.
LDBL_MAX_10_EXP The maximum integer n, such that 10n is a finite representable value of type long double.
LDBL_MAX_EXP The maximum integer n, such that LDBL_RADIXn-1 is a finite representable value of type long double.
LDBL_MIN The smallest normalized, finite representable value of type long double.
LDBL_MIN_10_EXP The minimum integer n, such that 10n is a normalized, finite representable value of type long double.
LDBL_MIN_EXP The minimum integer n, such that LDBL_RADIXn-1 is a normalized, finite representable value of type long double.
LDBL_RADIX The radix of all long double types.
LDBL_ROUNDS A value that describes the current rounding mode for long double operations.
  • -1 if the mode is indeterminate,
  • 0 if rounding is toward zero (this is the default for the Cx51 Compiler),
  • 1 if rounding is to nearest representable value,
  • 2 if rounding is toward +infinity,
  • 3 if rounding is toward -infinity.
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