Negated boolean names

IDNAMING-3
TitleNegated boolean variable names shall be avoided.
PriorityStrongly recommended
DescriptionAvoid variable names including the word not. Readability decreases when variables have negated boolean names.
RationaleReadability

Avoid:

if ~notValid && isNotFound
    error('My error message.')
end

Instead use:

if isValid && ~isFound
    error('My error message.')
end