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Scales argument by a power of 2.

double _scalb(
   double x,
   long exp 


Double-precision, floating-point value.


Long integer exponent.

Returns an exponential value if successful. On overflow (depending on the sign of x), _scalb returns +/– HUGE_VAL; the errno variable is set to ERANGE.

For more information about this and other return codes, see _doserrno, errno, _sys_errlist, and _sys_nerr.

The _scalb function calculates the value of x * 2exp.


Required header



For more compatibility information, see Compatibility in the Introduction.

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.