Magnetic recording has now played an important role in the development of non-volatile information storage technologies, so it becomes essential to quantitatively understand the magnetization distribution in magnetic microstructures.In ferromagnetic disks, squares and triangles with submicron sizes, it is energetically favorable for the magnetization to form a closed in-plane vortex and a perpendicular vortex core at the center. This vortex magnetic structure is a new candidate for future magnetic memory de...