How to use MATLAB software to draw graphs of known graphs

Method steps

1, the first step to extract the graph as many features points, recommend a software GetData2.2, many sites to provide this software download, download down after installation to open this software.

2, choose File->open Image, open the desired graph, choose Operations->set the scale, set the picture coordinate system, this step is very critical, can not be wrong.

3, the choice of Operations->digitize area, set a reasonable spacing, the smaller the distance, the more feature points extracted, the structure of the curve and the original curve of the fitting is higher. Red for the extraction of good curved segments, the coordinates of the feature points are shown on the right.

4, select File->export data, generate the TXT document containing the feature point, open the MATLAB software, write the program, introduce the feature point, and simply deal with it.

5, run the program, you can see the MATLAB generated graphics and the original curve is very similar, you can choose to fit the function further processing.