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copied!<p>If you want high performance with a minimal code footprint, look no farther than Python's built-in plotting library tkinter. No need to write special C / C++ code or use a large plotting package to get performance much better than 50 fps.</p> <p><img src="https://i.stack.imgur.com/CGK8y.png" alt="Screenshot"></p> <p>The following code scrolls a 1000x200 strip chart at 400 fps on a 2.2 GHz Core 2 duo, 1000 fps on a 3.4 GHz Core i3. The central routine "scrollstrip" plots a set of data points and corresponding colors at the right edge along with an optional vertical grid bar, then scrolls the stripchart to the left by 1. To plot horizontal grid bars just include them in the data and color arrays as constants along with your variable data points.</p> <pre><code>from tkinter import * import math, random, threading, time class StripChart: def __init__(self, root): self.gf = self.makeGraph(root) self.cf = self.makeControls(root) self.gf.pack() self.cf.pack() self.Reset() def makeGraph(self, frame): self.sw = 1000 self.h = 200 self.top = 2 gf = Canvas(frame, width=self.sw, height=self.h+10, bg="#002", bd=0, highlightthickness=0) gf.p = PhotoImage(width=2*self.sw, height=self.h) self.item = gf.create_image(0, self.top, image=gf.p, anchor=NW) return(gf) def makeControls(self, frame): cf = Frame(frame, borderwidth=1, relief="raised") Button(cf, text="Run", command=self.Run).grid(column=2, row=2) Button(cf, text="Stop", command=self.Stop).grid(column=4, row=2) Button(cf, text="Reset", command=self.Reset).grid(column=6, row=2) self.fps = Label(cf, text="0 fps") self.fps.grid(column=2, row=4, columnspan=5) return(cf) def Run(self): self.go = 1 for t in threading.enumerate(): if t.name == "_gen_": print("already running") return threading.Thread(target=self.do_start, name="_gen_").start() def Stop(self): self.go = 0 for t in threading.enumerate(): if t.name == "_gen_": t.join() def Reset(self): self.Stop() self.clearstrip(self.gf.p, '#345') def do_start(self): t = 0 y2 = 0 tx = time.time() while self.go: y1 = 0.2*math.sin(0.02*math.pi*t) y2 = 0.9*y2 + 0.1*(random.random()-0.5) self.scrollstrip(self.gf.p, (0.25+y1, 0.25, 0.7+y2, 0.6, 0.7, 0.8), ( '#ff4', '#f40', '#4af', '#080', '#0f0', '#080'), "" if t % 65 else "#088") t += 1 if not t % 100: tx2 = time.time() self.fps.config(text='%d fps' % int(100/(tx2 - tx))) tx = tx2 # time.sleep(0.001) def clearstrip(self, p, color): # Fill strip with background color self.bg = color # save background color for scroll self.data = None # clear previous data self.x = 0 p.tk.call(p, 'put', color, '-to', 0, 0, p['width'], p['height']) def scrollstrip(self, p, data, colors, bar=""): # Scroll the strip, add new data self.x = (self.x + 1) % self.sw # x = double buffer position bg = bar if bar else self.bg p.tk.call(p, 'put', bg, '-to', self.x, 0, self.x+1, self.h) p.tk.call(p, 'put', bg, '-to', self.x+self.sw, 0, self.x+self.sw+1, self.h) self.gf.coords(self.item, -1-self.x, self.top) # scroll to just-written column if not self.data: self.data = data for d in range(len(data)): y0 = int((self.h-1) * (1.0-self.data[d])) # plot all the data points y1 = int((self.h-1) * (1.0-data[d])) ya, yb = sorted((y0, y1)) for y in range(ya, yb+1): # connect the dots p.put(colors[d], (self.x,y)) p.put(colors[d], (self.x+self.sw,y)) self.data = data # save for next call def main(): root = Tk() root.title("StripChart") app = StripChart(root) root.mainloop() main() </code></pre>

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