Large reservoir-oriented flood inundation object index rapid calculation method

The invention provides a large reservoir-oriented flood inundation physical index rapid calculation method. The method comprises the following steps of generating a section hydro-fluctuation limit range polygon and a section inundation limit range polygon of each river section; generating grid points with elevation, grid area, administrative division, section and land type; building facility point data with section, administrative division, area, population and elevation information is generated; performing submerging index preprocessing according to the administrative regions and the water levels one by one according to the sections to form a submerging result table; and inputting the actual water level data into the inundation result table to obtain the flood inundation physical index of the river section under the actual water level data. The method has double advantages of high calculation precision and simple calculation. According to the method, the flood inundation real object index can be quickly calc