gmx::test::FloatingPointDifference Class Reference

#include <testutils/testasserts.h>

Description

Computes and represents a floating-point difference value.

Methods in this class do not throw, except for toString(), which may throw std::bad_alloc.

See Also

FloatingPointTolerance

Public Member Functions
	FloatingPointDifference (float ref, float value)
	Initializes a single-precision difference. More...
	FloatingPointDifference (double ref, double value)
	Initializes a double-precision difference. More...
bool	isNaN () const
	Whether one or both of the compared values were NaN. More...
double	asAbsolute () const
	Returns the difference as an absolute number (always non-negative).
gmx_uint64_t	asUlps () const
	Returns the difference as ULPs (always non-negative). More...
bool	signsDiffer () const
	Whether the compared values were of different sign. More...
bool	isDouble () const
	Whether the difference is between single- or double-precision numbers.
std::string	toString () const
	Formats the difference as a string for assertion failure messages.
double	termMagnitude () const
	Returns the magnitude of the original second term of the difference.

Constructor & Destructor Documentation

gmx::test::FloatingPointDifference::FloatingPointDifference	(	float	ref,
		float	value
	)

Initializes a single-precision difference.

Parameters

ref	First term in difference
value	Second term in difference

For absolute and ULP differences the two parameters are equivalent, since the difference is symmetric. For relative differences the first term is interpreted as the reference value, from which we extract the magnitude to compare with.

gmx::test::FloatingPointDifference::FloatingPointDifference	(	double	ref,
		double	value
	)

Initializes a double-precision difference.

Parameters

ref	First term in difference
value	Second term in difference

For absolute and ULP differences the two parameters are equivalent, since the difference is symmetric. For relative differences the first term is interpreted as the reference value, from which we extract the magnitude to compare with.

Member Function Documentation

gmx_uint64_t gmx::test::FloatingPointDifference::asUlps ( ) const

inline

Returns the difference as ULPs (always non-negative).

The ULPs are calculated for the type that corresponds to the constructor used to initialize the difference. The ULP difference between 0.0 and -0.0 is zero.

bool gmx::test::FloatingPointDifference::isNaN

(

)

const

Whether one or both of the compared values were NaN.

If this returns true, other accessors return meaningless values.

bool gmx::test::FloatingPointDifference::signsDiffer ( ) const

inline

Whether the compared values were of different sign.

0.0 and -0.0 are treated as positive and negative, respectively.

---

The documentation for this class was generated from the following files:

• src/testutils/testasserts.h
• src/testutils/testasserts.cpp