R language plot visualization: the visualization model creates a grid in the classification contour (contour) and meshgrid of the entire data space, in which the distance between each point is determi

R Language plotly visualization ： Use plotly The Classification Outline of the visual model in the whole data space （ contour ）、 Use meshgrid Create a grid , The distance between each point is determined by mesh_size Variable representation 、 Use different shape labels to represent 、 Training set 、 Test set 、 And classification labels of data sets