Another method of discrete point analysis is to analyze the discrete data to the grid point and then perform a curve fit or contour track of the grid point.
There are many common interpolation scenarios. Generally, it is more accurate to gradually revise and optimal interpolation. The optimal interpolation focuses on the physical or other relationship between the interpolated points, most accurate in all interpolation, and the physical meaning is clear. But sometimes it doesn't need to be so complex, or the information you provide is only one, there is no group of information that is related to each other. Here is a gradual revision method. It mainly includes a few steps 1, selecting the preparatory field 2, performing an objective analysis 3, the smoothing of the output information
Among them, the minds of mind are the use of actual information and preparatory venues to change and revised preparatory venues or initial value fields, get a new field, seeking the difference between the new field and the actual value, to revocation the last field, Until the revised field approximation so far. When the grid point of the data retention analysis is too far, the initial value will not change. For the area within the mesh point, you can use the quadratic interpolation, you should be more familiar, no more detailed. For points other than the selected grid area, use the CRESSMAN interpolation. CRESSMAN interpolation weight coefficient is Wij = (i ** 2-d ** 2) / (ri ** 2 d ** 2) When D <= ri is d> = ri, Wij = 0 where Ri is influence, D is the 2 or 3D distance of the discrete point to the grid point. After each comparing interpolation and actual data, a revised value is generated, and the next step can be performed until the error of the correction value and the actual data have reached the accuracy you satisfied. Generally fixed 10 is enough. The obtained grid is then nested. The tracking of the contour line and the slightly different triangle, the tracking equivalent point and the triangular are basically the same, mainly in the position of the contour line. Whenever the rectangle has an equal value point, there are several cases of the triangle, there are several situations, and there are three exports of the equivalent lines that require attention to the record and tracking of the elevation point. The judgment of the starting point also needs attention
