wind.fit_int is used internally by wind.dl to transform downloaded data from GFS. wind.fit_int applies trigonometry tools to transform U and V vector wind components in wind direction and speed features. It also transforms 0-360 longitude notation obtained from GFS data into -180/180 longitude notation. Moreover, it cleans dates names and sorts the data by latitude.
wind.fit_int(tmpx)downloaded data by wind.dl function from "rWind" package.
data.frame
https://en.wikipedia.org/wiki/Cross_product