Difference between revisions of "cpp/numeric/fenv/feraiseexcept"
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{{ddcl list header | cfenv}} | {{ddcl list header | cfenv}} | ||
{{ddcl list item | notes={{mark since c++11}} | | {{ddcl list item | notes={{mark since c++11}} | | ||
| − | int feraiseexcept(int excepts); | + | int feraiseexcept( int excepts ); |
}} | }} | ||
{{ddcl list end}} | {{ddcl list end}} | ||
| − | Attempts to raise all floating point exceptions listed in {{tt|excepts}} (a bitwise OR of the [[cpp/numeric/fenv/FE_exceptions|floating point exception macros]]). If one of the exceptions is FE_OVERFLOW or FE_UNDERFLOW, this function may additionally raise FE_INEXACT. The order in which the exceptions are raised is unspecified, except that FE_OVERFLOW and FE_UNDERFLOW are always raised before FE_INEXACT. | + | Attempts to raise all floating point exceptions listed in {{tt|excepts}} (a bitwise OR of the [[cpp/numeric/fenv/FE_exceptions|floating point exception macros]]). If one of the exceptions is {{c|FE_OVERFLOW}} or {{c|FE_UNDERFLOW}}, this function may additionally raise {{c|FE_INEXACT}}. The order in which the exceptions are raised is unspecified, except that {{c|FE_OVERFLOW}} and {{c|FE_UNDERFLOW}} are always raised before {{c|FE_INEXACT}}. |
===Parameters=== | ===Parameters=== | ||
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<< (r?"fails":"succeeds") << " and results in\n"; | << (r?"fails":"succeeds") << " and results in\n"; | ||
int e = std::fetestexcept(FE_ALL_EXCEPT); | int e = std::fetestexcept(FE_ALL_EXCEPT); | ||
| − | if(e & FE_DIVBYZERO) | + | if (e & FE_DIVBYZERO) { |
std::cout << "division by zero\n"; | std::cout << "division by zero\n"; | ||
| − | if(e & FE_INEXACT) | + | } |
| + | if (e & FE_INEXACT) { | ||
std::cout << "inexact\n"; | std::cout << "inexact\n"; | ||
| − | if(e & FE_INVALID) | + | } |
| + | if (e & FE_INVALID) { | ||
std::cout << "invalid\n"; | std::cout << "invalid\n"; | ||
| − | if(e & FE_UNDERFLOW) | + | } |
| + | if (e & FE_UNDERFLOW) { | ||
std::cout << "underflow\n"; | std::cout << "underflow\n"; | ||
| − | if(e & FE_OVERFLOW) | + | } |
| + | if (e & FE_OVERFLOW) { | ||
std::cout << "overflow\n"; | std::cout << "overflow\n"; | ||
| − | + | } | |
} | } | ||
| output= | | output= | ||
Revision as of 03:22, 17 June 2012
Template:ddcl list begin <tr class="t-dsc-header">
<td>Defined in header
</td>
<cfenv>
<td></td> <td></td> </tr> <tr class="t-dcl ">
<td >int feraiseexcept( int excepts );
</td>
<td class="t-dcl-nopad"> </td> <td > (since C++11) </td> </tr> Template:ddcl list end
Attempts to raise all floating point exceptions listed in excepts (a bitwise OR of the floating point exception macros). If one of the exceptions is FE_OVERFLOW or FE_UNDERFLOW, this function may additionally raise FE_INEXACT. The order in which the exceptions are raised is unspecified, except that FE_OVERFLOW and FE_UNDERFLOW are always raised before FE_INEXACT.
Contents |
Parameters
| excepts | - | bitmask listing the exception flags to raise |
Return value
0 if all listed exceptions were raised, non-zero value otherwise.
Example
Run this code
#include <iostream> #include <cfenv> #pragma STDC FENV_ACCESS ON int main() { std::feclearexcept(FE_ALL_EXCEPT); int r = std::feraiseexcept(FE_UNDERFLOW | FE_DIVBYZERO); std::cout << "Raising divbyzero and underflow simultaneously " << (r?"fails":"succeeds") << " and results in\n"; int e = std::fetestexcept(FE_ALL_EXCEPT); if (e & FE_DIVBYZERO) { std::cout << "division by zero\n"; } if (e & FE_INEXACT) { std::cout << "inexact\n"; } if (e & FE_INVALID) { std::cout << "invalid\n"; } if (e & FE_UNDERFLOW) { std::cout << "underflow\n"; } if (e & FE_OVERFLOW) { std::cout << "overflow\n"; } }
Output:
Raising divbyzero and underflow simultaneously succeeds and results in division by zero underflow
