ssinint

Shifted sine integral, Si(x) - pi/2.

Category: Mathematics > Mathematical Functions

Syntax

Y = ssinint(x)

Description

The shifted sine integral is ssinint(x) = sinint(x) - pi/2. It goes to 0 as x goes to +Inf and to -pi at -Inf, so it is the natural form when the interest is in the tail of Si, avoiding cancellation between two numbers close to pi/2.

Input arguments

x

Real or complex scalar or array.

Output arguments

Y

Values of the function, with the size of x.

Example

Compare with sinint

ssinint([0 1 Inf])
sinint(1) - pi/2

ans = 1×3

   -1.5708   -0.6247         0
ans = -0.6247

See also

sinint sinhint cosint expint