import pyglet
import math
 
window = pyglet.window.Window()
window.set_caption("Test graph")
 
title = pyglet.text.Label('Test Graph',
                          font_name='Arkhip',
                          font_size=12,
                          x=window.width//2, y=window.height//2,
                          anchor_x='center', anchor_y='top')

                 
def round_sig(x, sig=2):
    return round(x, sig-int(math.floor(math.log10(abs(x))))-1)
                 
def drawgrid(xlines, ylines, xlimits, ylimits):
    for xpos in range(0, window.width, window.width/xlines):
        pyglet.graphics.draw(2, pyglet.gl.GL_LINES, ('v2i', (xpos, 0, xpos, window.height)))
        tagtext = str(round((xlimits[1]-xlimits[0])*(float(xpos)/window.width), 1))
        tag = pyglet.text.Label(tagtext, font_name='Arkhip', font_size=10, x=xpos-2, y=0, anchor_x='right', anchor_y='bottom')
        tag.draw()
    for ypos in range(0, window.width, window.width/ylines):
        pyglet.graphics.draw(2, pyglet.gl.GL_LINES, ('v2i', (0, ypos, window.width, ypos)))
        tagtext = str(round((ylimits[1]-ylimits[0])*(float(ypos)/window.height), 1))
        tag = pyglet.text.Label(tagtext, font_name='Arkhip', font_size=10, x=0, y=ypos-2, anchor_x='left', anchor_y='top')
        tag.draw()


def plotline(xdata, ydata):
    pass


xdata = [1, 2, 3, 4, 5, 6, 7, 7.4, 9, 10]
ydata = [81, 86, 58, 20, 59, 3, -6, 4.8]

@window.event
def on_draw():
    window.clear()
    drawgrid(10, 12, [min(xdata), max(xdata)], [min(ydata), max(ydata)])
    
pyglet.app.run()