Floating-point environment. Handling of floating-point rounding and exceptions (overflow, division by zero, etc.). The types, vars and procs are bindings for the C standard library <fenv.h> header.
Types
Tfenv {.importc: "fenv_t", header: "<fenv.h>", final, pure.} = object
- Represents the entire floating-point environment. The floating-point environment refers collectively to any floating-point status flags and control modes supported by the implementation. Source Edit
Tfexcept {.importc: "fexcept_t", header: "<fenv.h>", final, pure.} = object
- Represents the floating-point status flags collectively, including any status the implementation associates with the flags. A floating-point status flag is a system variable whose value is set (but never cleared) when a floating-point exception is raised, which occurs as a side effect of exceptional floating-point arithmetic to provide auxiliary information. A floating-point control mode is a system variable whose value may be set by the user to affect the subsequent behavior of floating-point arithmetic. Source Edit
Vars
FE_ALL_EXCEPT: cint
- bitwise OR of all supported exceptions Source Edit
FE_DFL_ENV: cint
- macro of type pointer to fenv_t to be used as the argument to functions taking an argument of type fenv_t; in this case the default environment will be used Source Edit
FE_DIVBYZERO: cint
- division by zero Source Edit
FE_DOWNWARD: cint
- round toward -Inf Source Edit
FE_INEXACT: cint
- inexact result Source Edit
FE_INVALID: cint
- invalid operation Source Edit
FE_OVERFLOW: cint
- result not representable due to overflow Source Edit
FE_TONEAREST: cint
- round to nearest Source Edit
FE_TOWARDZERO: cint
- round toward 0 Source Edit
FE_UNDERFLOW: cint
- result not representable due to underflow Source Edit
Procs
proc feclearexcept(excepts: cint): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Clear the supported exceptions represented by excepts. Source Edit
proc fegetenv(envp: ptr Tfenv): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Store the current floating-point environment in the object pointed to by envp. Source Edit
proc fegetexceptflag(flagp: ptr Tfexcept; excepts: cint): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Store implementation-defined representation of the exception flags indicated by excepts in the object pointed to by flagp. Source Edit
proc fegetround(): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Get current rounding direction. Source Edit
proc feholdexcept(envp: ptr Tfenv): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Save the current environment in the object pointed to by envp, clear exception flags and install a non-stop mode (if available) for all exceptions. Source Edit
proc feraiseexcept(excepts: cint): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Raise the supported exceptions represented by excepts. Source Edit
proc fesetenv(a1: ptr Tfenv): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Establish the floating-point environment represented by the object pointed to by envp. Source Edit
proc fesetexceptflag(flagp: ptr Tfexcept; excepts: cint): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Set complete status for exceptions indicated by excepts according to the representation in the object pointed to by flagp. Source Edit
proc fesetround(roundingDirection: cint): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Establish the rounding direction represented by roundingDirection. Source Edit
proc fetestexcept(excepts: cint): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Determine which of subset of the exceptions specified by excepts are currently set. Source Edit
proc feupdateenv(envp: ptr Tfenv): cint {.importc, header: "<fenv.h>", ...raises: [], tags: [].}
- Save current exceptions in temporary storage, install environment represented by object pointed to by envp and raise exceptions according to saved exceptions. Source Edit
Templates
template digits(T: typedesc[float32]): int
- Number of decimal digits that can be represented in a 32-bit floating-point type without losing precision. Source Edit
template digits(T: typedesc[float64]): int
- Number of decimal digits that can be represented in a 64-bit floating-point type without losing precision. Source Edit
template epsilon(T: typedesc[float32]): float32
- The difference between 1.0 and the smallest number greater than 1.0 that can be represented in a 32-bit floating-point type. Source Edit
template epsilon(T: typedesc[float64]): float64
- The difference between 1.0 and the smallest number greater than 1.0 that can be represented in a 64-bit floating-point type. Source Edit
template fpRadix(): int
- The (integer) value of the radix used to represent any floating point type on the architecture used to build the program. Source Edit
template mantissaDigits(T: typedesc[float32]): int
- Number of digits (in base floatingPointRadix) in the mantissa of 32-bit floating-point numbers. Source Edit
template mantissaDigits(T: typedesc[float64]): int
- Number of digits (in base floatingPointRadix) in the mantissa of 64-bit floating-point numbers. Source Edit
template max10Exponent(T: typedesc[float32]): int
- Maximum (positive) exponent in base 10 for 32-bit floating-point numbers. Source Edit
template max10Exponent(T: typedesc[float64]): int
- Maximum (positive) exponent in base 10 for 64-bit floating-point numbers. Source Edit
template maxExponent(T: typedesc[float32]): int
- Maximum (positive) exponent for 32-bit floating-point numbers. Source Edit
template maxExponent(T: typedesc[float64]): int
- Maximum (positive) exponent for 64-bit floating-point numbers. Source Edit
template maximumPositiveValue(T: typedesc[float32]): float32
- The largest positive number that can be represented in a 32-bit floating-point type. Source Edit
template maximumPositiveValue(T: typedesc[float64]): float64
- The largest positive number that can be represented in a 64-bit floating-point type. Source Edit
template min10Exponent(T: typedesc[float32]): int
- Minimum (negative) exponent in base 10 for 32-bit floating-point numbers. Source Edit
template min10Exponent(T: typedesc[float64]): int
- Minimum (negative) exponent in base 10 for 64-bit floating-point numbers. Source Edit
template minExponent(T: typedesc[float32]): int
- Minimum (negative) exponent for 32-bit floating-point numbers. Source Edit
template minExponent(T: typedesc[float64]): int
- Minimum (negative) exponent for 64-bit floating-point numbers. Source Edit