Let's consider a code example showing what would be allowed (or not) using different levels of inheritance: 1  class BaseClass {}; void freeStandingFunction(BaseClass* b); class DerivedProtected : protected BaseClass { DerivedProtected() { freeStandingFunction(this); // Allowed } };
Definition of Horizontal Axis. Horizontal means flat or level. Horizontal axis is the x-axis on a graph. The blue number line in the figure below is the x-axis, the horizontal axis.
In x-y plots, like the one above, the x-axis runs horizontally (flat). Typically, the x-axis has numbers representing different time periods or names of things being measured. In this plot, the x-axis measures the amount of money spent by a country on elementary and secondary education per child.