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exp10
Base 10 exponential function. (Common antilogarithm.)SYNOPSIS:
double x, y, exp10();
y = exp10(x);
DESCRIPTION:
Returns 10 raised to the x power.
Range reduction is accomplished by expressing the argument as 10**x = 2**n 10**f, with |f| < 0.5 log10(2).
The Pade' form:
1 + 2x P(x**2)/(Q(x**2) - P(x**2))
is used to approximate 10**f.
ACCURACY:
Relative error:
arithmetic domain # trials peak rms
IEEE -307,+307 30000 2.2e-16 5.5e-17
Test result from an earlier version (2.1):
DEC -38,+38 70000 3.1e-17 7.0e-18
ERROR MESSAGES:
message condition value returned
underflow x < -MAXL10 0.0
overflow x > MAXL10 MAXNUM
DEC arithmetic: MAXL10 = 38.230809449325611792.
IEEE arithmetic: MAXL10 = 308.2547155599167.