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+--- Thread: Limitation of function EXP() (/showthread.php?tid=1495)
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RE: Limitation of function EXP() - RhoSigma - 02-23-2023
I've updated the EXP wiki page, but there's a limit for type _FLOAT too (709,....).
However, you don't necessarily need to DIM AS _FLOAT, you can also specify literal numbers as _FLOAT by appending the respective type suffix (##) to the number, e.g. EXP(567.89##)
RE: Limitation of function EXP() - Jack - 02-23-2023
(02-22-2023, 06:27 PM)SMcNeill Wrote:Code: (Select All)// EXP
double func_exp_single(double value) {
if (value <= 88.02969) {
return exp(value);
}
error(6);
return 0;
}
long double func_exp_float(long double value) {
if (value <= 709.782712893) {
return exp(value);
}
error(6);
return 0;
}
@SMcNeill
in this statement: if (value <= 709.782712893)
what if value is -11356 for example?
I think that it needs to be something like the following
Code: (Select All)
long double func_exp_float(long double value) {
if (fabsl(value) <= 11355) {
return exp(value);
}
error(6);
return 0;
}RE: Limitation of function EXP() - jcm - 02-23-2023
(02-23-2023, 02:57 PM)Jack Wrote:The limitation is with the definition of the maximum double 1.7976E+308(02-22-2023, 06:27 PM)SMcNeill Wrote:Code: (Select All)// EXP
double func_exp_single(double value) {
if (value <= 88.02969) {
return exp(value);
}
error(6);
return 0;
}
long double func_exp_float(long double value) {
if (value <= 709.782712893) {
return exp(value);
}
error(6);
return 0;
}
@SMcNeill
in this statement: if (value <= 709.782712893)
what if value is -11356 for example?
I think that it needs to be something like the following
Code: (Select All)long double func_exp_float(long double value) {
if (fabsl(value) <= 11355) {
return exp(value);
}
error(6);
return 0;
}
the maximum number = ln(1.7976E308)=709.78177061
RE: Limitation of function EXP() - RhoSigma - 02-23-2023
Once again updated/clarified the EXP wiki page. Got a bit confused by the C++ function names respectively passed parameter types.
In fact @Jack was right, EXP is not really supporting _FLOAT precision, although you may pass such a value, it's still limited to 709.something, as DOUBLE runs through the same C++ function and so the limit of the smaller type must be taken.