MathWorks Support Team (view profile) MATLAB does not recognize the specified string as the name of a function on the MATLAB path or a variable visible to that function. - a typographical error when typing a command or variable name (such as typing a 1 [one] when you intended to type an l [low-case L]).
Blood tests can detect cocaine itself for about 12 hours after use. Urine tests check for metabolic byproducts of cocaine, and in infrequent users a urine test is positive for up to two to three days after cocaine use.
Cocaine is detectable by standard drug tests on urine up to 72 hours after use. Long-term, habitual users may have traces of cocaine in their system for longer than the standard three days.The level of concentration that triggers a positive result for coke use is 300 ng/ml.his method is more expensive than conducting a urine test. The average cost of this method is in the $100-$150 range. A person is more likely to test positive on a hair test than one using a urine sample. A hair sample test for cocaine can detect the presence of the drug quite readily.