QwtScaleArithmetic Class Reference

Arithmetic including a tolerance. More...

#include <qwt_scale_engine.h>

List of all members.

Static Public Member Functions

static int compareEps (double value1, double value2, double intervalSize)
static double ceilEps (double value, double intervalSize)
static double floorEps (double value, double intervalSize)
static double divideEps (double interval, double steps)
static double ceil125 (double x)
static double floor125 (double x)

Detailed Description

Arithmetic including a tolerance.


Member Function Documentation

double QwtScaleArithmetic::ceil125 ( double  x  )  [static]

Find the smallest value out of {1,2,5}*10^n with an integer number n which is greater than or equal to x

Parameters:
x Input value
double QwtScaleArithmetic::ceilEps ( double  value,
double  intervalSize 
) [static]

Ceil a value, relative to an interval

Parameters:
value Value to ceil
intervalSize Interval size
See also:
floorEps()
int QwtScaleArithmetic::compareEps ( double  value1,
double  value2,
double  intervalSize 
) [static]

Compare 2 values, relative to an interval.

Values are "equal", when : $\cdot value2 - value1 <= abs(intervalSize * 10e^{-6})$

Parameters:
value1 First value to compare
value2 Second value to compare
intervalSize interval size
Returns:
0: if equal, -1: if value2 > value1, 1: if value1 > value2
double QwtScaleArithmetic::divideEps ( double  intervalSize,
double  numSteps 
) [static]

Divide an interval into steps.

$stepSize = (intervalSize - intervalSize * 10e^{-6}) / numSteps$

Parameters:
intervalSize Interval size
numSteps Number of steps
Returns:
Step size
double QwtScaleArithmetic::floor125 ( double  x  )  [static]

Find the largest value out of {1,2,5}*10^n with an integer number n which is smaller than or equal to x.

Parameters:
x Input value
double QwtScaleArithmetic::floorEps ( double  value,
double  intervalSize 
) [static]

Floor a value, relative to an interval

Parameters:
value Value to floor
intervalSize Interval size
See also:
floorEps()
Generated on Sun Apr 11 11:56:19 2010 for Qwt User's Guide by  doxygen 1.6.3