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#include "AdunKernel/AdunConfigurationGenerator.h"
@implementation AdConfigurationGenerator
- (void) checkFloatingPointErrors
{
int raised;
NSMutableDictionary* errorInfo;
NSError* error;
/*
* We want to detect floating point errors since they
* will affect the stability of our simulation.
* The errors we are detecting are based on IEEE754 standard
* 1 - Invalid Operation
* 2 - Division by Zero
* 3 - Overflow
* 4 - Underflow
* 5 - Inexact
* However error 5 is common since all irrational and transcendental
* numbers are inexact and we may be adding many numbers who differ by more than
* DBL_EPSILON so we wont do anything in this case .
* Error 4 leads to a slow loss of precision - however it may occur
* that tiny forces and energies are calculated in the course of
* a simulation. In this case we will just log when this happens and
* let Error 2 handle cases where this will lead to a catastrophic error
* (due to the result being zero).
* See the Arithmetic section of the libc manual for more detail.
*/
raised = fetestexcept(AdFloatingPointExceptionMask);
#ifdef FE_INVALID
if(raised & FE_INVALID)
{
errorInfo = [NSMutableDictionary dictionary];
[errorInfo setObject: @"Detected floating point exception during simulation."
forKey: NSLocalizedDescriptionKey];
[errorInfo setObject: @"Exception due to an invalid operation."
forKey: @"AdDetailedDescriptionKey"];
[errorInfo setObject: @"This is a critical error and likely due to a bug in an underlying algorithm.\n\
Please contact the Adun developers with information regarding the simulation you were running when this occurred.\n\
(Options, System, Results etc)\n"
forKey: @"NSRecoverySuggestionKey"];
error = [NSError errorWithDomain: AdunKernelErrorDomain
code: AdKernelFloatingPointError
userInfo: errorInfo];
feclearexcept(FE_ALL_EXCEPT);
[[NSException exceptionWithName: @"AdFloatingPointException"
reason: @"Caught a IEEE74 floating point exception"
userInfo: [NSDictionary dictionaryWithObject: error
forKey: @"AdKnownExceptionError"]]
raise];
}
#endif
#ifdef FE_OVERFLOW
if(raised & FE_OVERFLOW)
{
errorInfo = [NSMutableDictionary dictionary];
[errorInfo setObject: @"Detected floating point exception during simulation."
forKey: NSLocalizedDescriptionKey];
[errorInfo setObject: @"Exception due to overflow"
forKey: @"AdDetailedDescriptionKey"];
[errorInfo setObject: @"This error indicates infinities entering the simulation.\n\
This is likely an indication of the simulation exploding due to excessive forces.\nUnrelaxed starting structures are\
a possible explanation.\nIn this case it is recommended you run an initial simulation with a smaller time step to relax\
the molecule.\nIt is also recommened that you examine the data collected so far which will provide more information on\
the cause.\n)"
forKey: @"NSRecoverySuggestionKey"];
error = [NSError errorWithDomain: AdunKernelErrorDomain
code: AdKernelFloatingPointError
userInfo: errorInfo];
feclearexcept(FE_ALL_EXCEPT);
[[NSException exceptionWithName: @"AdFloatingPointException"
reason: @"Caught a IEEE74 floating point exception"
userInfo: [NSDictionary dictionaryWithObject: error
forKey: @"AdKnownExceptionError"]]
raise];
}
#endif
#ifdef FE_DIVBYZERO
if(raised & FE_DIVBYZERO)
{
errorInfo = [NSMutableDictionary dictionary];
[errorInfo setObject: @"Detected floating point exception during simulation."
forKey: NSLocalizedDescriptionKey];
[errorInfo setObject: @"Exception due to divide by zero"
forKey: @"AdDetailedDescriptionKey"];
[errorInfo setObject: @"This error could be due to a underflow event or a programming bug.\n\
Please contact the Adun developers with information regarding the simulation you were running when this occurred.\n\
(Options, System, Results etc)\n"
forKey: @"NSRecoverySuggestionKey"];
error = [NSError errorWithDomain: AdunKernelErrorDomain
code: AdKernelFloatingPointError
userInfo: errorInfo];
feclearexcept(FE_ALL_EXCEPT);
[[NSException exceptionWithName: @"AdFloatingPointException"
reason: @"Caught a IEEE74 floating point exception"
userInfo: [NSDictionary dictionaryWithObject: error
forKey: @"AdKnownExceptionError"]]
raise];
}
#endif
#ifdef FE_UNDERFLOW
if(raised & FE_UNDERFLOW)
{
NSWarnLog(@"Detected an underflow exception.");
NSWarnLog(@"This could be the result of extremly small forces and/or energies being calculated.");
NSWarnLog(@"Such events are not uncommon but will lead to a loss of precision.");
NSWarnLog(@"It is possible that underflows could lead to zeros entering the calculation and\
'divide by zero' errors as a result\n. However these will be caught independantly if they occur");
NSWarnLog(@"Continuing simulation");
feclearexcept(FE_ALL_EXCEPT);
}
#endif
//clear any FE_INEXACT exceptions
feclearexcept(FE_ALL_EXCEPT);
}
- (BOOL) production: (NSError**) error
{
NSWarnLog(@"Abstract method. You should only initialise a concrete subclass of %@",
NSStringFromClass([self class]));
}
- (BOOL) restartFrom: (int) step error: (NSError**) error
{
NSWarnLog(@"Abstract method. You should only initialise a concrete subclass of %@",
NSStringFromClass([self class]));
}
- (void) endProduction
{
NSWarnLog(@"Abstract method. You should only initialise a concrete subclass of %@",
NSStringFromClass([self class]));
}
- (unsigned int) numberOfSteps
{
NSWarnLog(@"Abstract method. You should only initialise a concrete subclass of %@",
NSStringFromClass([self class]));
}
- (void) setNumberOfSteps: (unsigned int) aNumber
{
NSWarnLog(@"Abstract method. You should only initialise a concrete subclass of %@",
NSStringFromClass([self class]));
}
- (unsigned int) currentStep
{
NSWarnLog(@"Abstract method. You should only initialise a concrete subclass of %@",
NSStringFromClass([self class]));
}
- (AdSystemCollection*) systems
{
NSWarnLog(@"%@ is an abstract method. You should only initialise a concrete subclass of %@",
NSStringFromSelector(_cmd),
NSStringFromClass([self class]));
}
- (AdForceFieldCollection*) forceFields
{
NSWarnLog(@"%@ is an abstract method. You should only initialise a concrete subclass of %@",
NSStringFromSelector(_cmd),
NSStringFromClass([self class]));
}
@end
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