Emetophobia in which the phobic person will go to great lengths to avoid even potential situations that could even be perceived as "threatening". Emetophobia is clinically considered an "elusive predicament" because limited research has been done pertaining to it. The fear of vomiting receives little attention compared with other irrational fears. Frank M. Dattilio. "Emetic Exposure and Desensitization Procedures in the Reduction of Nausea and a Fear of Emesis." "Clinical Case Studies" 2.3 (2003): 199-210.</ref> The event of vomiting may make anyone with this peculiar phobia flee the scene. Some may fear someone throwing up, while others may fear themselves throwing
Rational function the degree of formula_29 and both are real polynomials. The rational function is not defined at It is asymptotic to formula_32 as formula_33 The rational function is defined for all real numbers, but not for all complex numbers, since if "x" were a square root of formula_35 (i.e. the imaginary unit or its negative), then formal evaluation would lead to division by zero: which is undefined. A constant function such as "f"("x") = π is a rational function since constants are polynomials. Note that the function itself is rational, even though the value of "f"("x") is irrational for all "x".