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.
The y-axis on the wall is vertical but the one on the table is horizontal. In the 2-dimension case, as mentioned already, the usual designation of the vertical coincides with the y-axis in co-ordinate geometry. This convention can cause confusion in the classroom.