matplotlib 是什么

# pip install matplotlib==2.2.2

from kivy.garden.matplotlib.backend_kivyagg import FigureCanvasKivyAgg

FigureCanvasKivyAgg

class FigureCanvasKivyAgg(FigureCanvasKivy, FigureCanvasAgg):
    '''FigureCanvasKivyAgg class. See module documentation for more
    information.
    '''

    def __init__(self, figure, **kwargs):
        self.figure = figure
        self.bind(size=self._on_size_changed)
        super(FigureCanvasKivyAgg, self).__init__(figure=self.figure, **kwargs)
        self.img_texture = None
        self.img_rect = None
        self.blit()

    def draw(self):
        '''
        Draw the figure using the agg renderer
        '''
        self.canvas.clear()
        FigureCanvasAgg.draw(self)
        if self.blitbox is None:
            l, b, w, h = self.figure.bbox.bounds
            w, h = int(w), int(h)
            buf_rgba = self.get_renderer().buffer_rgba()
        else:
            bbox = self.blitbox
            l, b, r, t = bbox.extents
            w = int(r) - int(l)
            h = int(t) - int(b)
            t = int(b) + h
            reg = self.copy_from_bbox(bbox)
            buf_rgba = reg.to_string()
        texture = Texture.create(size=(w, h))
        texture.flip_vertical()
        color = self.figure.get_facecolor()
        with self.canvas:
            Color(*color)
            Rectangle(pos=self.pos, size=(w, h))
            Color(1.0, 1.0, 1.0, 1.0)
            self.img_rect = Rectangle(texture=texture, pos=self.pos,
                                      size=(w, h))
        texture.blit_buffer(bytes(buf_rgba), colorfmt='rgba', bufferfmt='ubyte')
        self.img_texture = texture

    filetypes = FigureCanvasKivy.filetypes.copy()
    filetypes['png'] = 'Portable Network Graphics'

    def _on_pos_changed(self, *args):
        if self.img_rect is not None:
            self.img_rect.pos = self.pos

    def _print_image(self, filename, *args, **kwargs):
        '''Write out format png. The image is saved with the filename given.
        '''
        l, b, w, h = self.figure.bbox.bounds
        img = None
        if self.img_texture is None:
            texture = Texture.create(size=(w, h))
            texture.blit_buffer(bytes(self.get_renderer().buffer_rgba()),
                                colorfmt='rgba', bufferfmt='ubyte')
            texture.flip_vertical()
            img = Image(texture)
        else:
            img = Image(self.img_texture)
        img.save(filename)