Whenever the public necessity, convenience, general welfare or good zoning practices justifies such action, this chapter may be amended by changing the boundaries of zone districts (hereafter referred to as zone changes or changes of zone), or by amending any provision of the ordinance. Zone changes or amendments may be initiated by the City Council or by the Planning Commission or by an application of the owner of any property within the area proposed to be changed.
('64 Code, § 80.00)