I'm having some trouble getting matplotlib to plot a graph if my Y values are all the same. I am plotting a graph of temperature against time, and I have found that if my temperatures are all the same I get no line plotted, as soon as a temperature change is added to the plot, the line is then drawn. I have been able to force it to draw the line always by initialising my list of temperatures with a value of zero (0), but that only works assuming the temperature isn't at zero for any time. Is there a way I can cause it to plot my graph properly without priming with fake values? Fields: temperature = [] time = [] minY = 0 maxY = 0 Setting (on sensor poll): temp = float(params['temp'][0]) time = datetime.now() self.temperature.append(temp) self.time.append(time) Plot: plt.figure() plt.xlabel("Time") plt.ylabel("Temperature (Celcius)") plt.title("Temperature in ...") plt.ylim(self.minY,self.maxY) plt.plot(self.time,self.temperature, "c") plt.gcf().autofmt_xdate() plt.savefig("temp.svg") Edit: If I set plot type to "o" (circles) when I call plot, I can see the circles on the same line, if I switch back to the default line type, I see nothing. Edit2: Switching output format to png produces the line correctly. Why is SVG not doing so? Continue reading...
