The optimum contour with polar co-ordinates (r as a function of φ) and complex length increment with φ (Evans and Chung, 2000)
1 2 3
width of the contour - too small and get too close to singularities on negative x-axis, too large and encounter instability for large positive x
standard (time) domain variable, also affects contour width
t is set as zero, it is changed to 5 (avoids dividing by 0)
Evans & Chung, 2000: Laplace transform inversions using optimal contours in the complex plane International Journal of Computer Mathematics v73 pp531-543.