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   ### About Matlab(STOP)(REPLACEED BY SPP_plot)
   * ~~When the new station data is needed for calculation, two parts of parameters in the Matlab source file need to be corrected, the first is the exact coordinates of the station in the file header, and the second is the longitude, latitude and elevation information of the station in the file header.(OINP)~~
   ### About PyPlot
-  * With the help of python's tkinter and matplotlib libraries, it is realized to read and process the.sp file generated by SPP_calculate and generate the.po file in the.sp sibling directory. The generated.po file can be processed by SPP_plot to obtain line plots of ENU components.
+  * With the help of python's tkinter and matplotlib libraries, it is realized to read and process the.sp file generated by SPP_calculate and generate the (.po file) in the (.sp file) sibling directory. The generated.po file can be processed by SPP_plot to obtain line plots of ENU components.
   * At present, the algorithm of station position calculation is integrated in the plot, and only two default tropospheric and ionospheric correction algorithms are supported at present, and the accuracy is still being optimized.
   * The format of the (.po file) is described in detail in the help documentation.