For fun_cmp(), if you provide both a tol and relTol value, the tol value will take precedence, so absolute tolerances will be used.
On the other hand, for num_cmp() and its brethren, supplying both tolerances will generate an error message. It would probably be good if fun_cmp() did the same.
If you use MathObjects, the tolerance type is set by using tolType=>"absolute" or tolType=>"relative", so there is no ambiguity, as there is no way to specify both at once.
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fun_cmp evaluation points
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