Question

在FORTRAN90中e如何表示

Answer 1

上边是指数，下边是对数
EXP
Elemental Intrinsic Function (Generic): Computes an exponential value.
Syntax
result = EXP (x)
x
(Input) Must be of type real or complex.
Results:
The result type is the same as x. The value of the result is e^x. If x is of type complex, its imaginary part is regarded as a value in radians.
LOG
Elemental Intrinsic Function (Generic): Returns the natural logarithm of the argument.
Syntax
result = LOG (x)
x
(Input) Must be of type real or complex. If x is real, its value must be greater than zero. If x is complex, its value must not be zero.
Results:
The result type is the same as x. The result value is approximately equal to log_e(x). If the arguments are complex, the result is the principal value of imaginary part omega in the range -pi < omega <= pi. The imaginary part of the result is pi if the real part of the argument is less than zero and the imaginary part of the argument is zero.