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This article mainly explains "how to calculate the simple data difference by javascript". Interested friends may wish to take a look. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn "how javascript calculates the simple data difference".

In the gridding data development of GIS, the data is distributed according to a certain interval, and the data on the grid point is easy to obtain. If you want to obtain the data value that is not in the grid point, it is necessary to calculate the difference according to the data of the point around this point.

In the use of meteorological data, a simple bilinear difference can be made according to the four points around a point.

According to the Abscissa and ordinate of the GIS data, the horizontal and vertical order of the grid where the points are provided is calculated, that is, in the grid, and the specific values of the four corners are obtained.

A simple example diagram (from the network) calculates the maximum and minimum row number by the difference in each grid:

The percentage of distance between the point and the four focal points is calculated, and then the data value of the point is calculated by simple multiplication and addition.

A simple sample code for JavaScript:

X and y are the percentages in the horizontal and vertical axes, respectively, and gXX is the specific data values of the four surrounding points.

Function bilinearInterpolate (x, y, G00, G10, G01, G11) {

Var rx = (1-x)

Var ry = (1-y)

Return G00 * rx * ry + G10 * x * ry + G01 * rx * y + G11 * x * y

}

Note: most of the gridded data are used to store meteorological data, and the common data format is netcdf,grib.

At this point, I believe you have a deeper understanding of "how to calculate the simple data difference in javascript". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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