Note that this is equivalent to replacing “size 1/0” with “size 1″. Issues with this become apparent if the scale of your system is much smaller or larger than 1. A better try might be to replace 0 with the average of the other eigenvalues, times a fudge factor. But still quite unprincipled—maybe better is to try to look at higher derivatives first or do nonlocal numerical estimation like described in the post.
Note that this is equivalent to replacing “size 1/0” with “size 1″. Issues with this become apparent if the scale of your system is much smaller or larger than 1. A better try might be to replace 0 with the average of the other eigenvalues, times a fudge factor. But still quite unprincipled—maybe better is to try to look at higher derivatives first or do nonlocal numerical estimation like described in the post.