Python Matplotlib-如何在X轴上绘制一条线？

Question

So I'm working on a new project where I'm using matplotlib to track my habits. The y-axis is a list of all my habits (the bottom is "retainer" and the top is "UAS" (my club meetings)). The x-axis are the numbers 1 - days in month (1-31 for January 2018 for example). I'm trying to lay a line behind the chart that will hide under the x-axis if no habits are completed, and will spike up equally to how many habits are completed on any specific day. My problem is that plotting the line at (0,x), or with correct syntax: plt.plot((0),(0)), actually plots it at what appears to be (1,1) or with my labels (1,"retainer"). Which would give the impression that at least one habit was completed.

In previous version of matplotlib it seems that there is no quarrel with graphing lines right up to the axis, but now an automatic "buffer" space is applied so you cant do that anymore.

I dont want to change that buffer space, I just want to graph my line on the x-axis when no habits are completed so that it does not show.

Current habits are just test data, which I mention because otherwise it would look kinda strange.

Here is a picture, followed by my code:

picture of plot, graph line is scale with completed habits (red), but is one element too high

and my code:

import matplotlib.pyplot as plt
import calendar
import datetime
import atexit

def main():
    global trackers
    activities = ["Retainer","Steps Goal","Drink Water","6+ Hours Sleep","<=2 Sodas","Study","Leave Campus","Clean","Mike","Paint","Phone Call","Saw Friends","UAS"]
    trackers = []
    completed = []
    days_in_month = calendar.monthrange(int(str(datetime.datetime.now())[0:4]),int(str(datetime.datetime.now())[5:7]))[1]
    current_day = int(str(datetime.datetime.now())[8:11])
    file = open("trackers.txt","r")
    data = file.readlines()
    for i in range(len(data)):
        data[i] = data[i].rstrip("\n").rstrip("").rstrip(",")
        trackers.append(data[i].split(","))
        for b in range(len(trackers[-1])):
            trackers[-1][b] = int(trackers[-1][b])
    print("Trackers Loaded")

    plt.switch_backend('TkAgg')

    for i in range(days_in_month):
        completed.append(0)
        for b in range(len(trackers)):
            completed[-1] += trackers[b][i]

    plt.plot(tuple([i for i in range(days_in_month)]), tuple(completed),c = "k")

    plt.axvline(x=current_day - 1, c="#ccf3ff", linewidth = 30, zorder = -1)
    plt.grid()

    plt.title("Habit Tracker")
    plt.yticks([i for i in range(len(trackers))],tuple(activities))
    plt.xticks([i for i in range(days_in_month)],[i for i in range(1,days_in_month + 1)])
    for i in range(len(trackers)):
        for b in range(days_in_month):
            if trackers[i][b] == 1:
                plt.plot(b,i,"rs", markersize = 8)
            else:
                plt.plot(b,i,"s", color = "#d2d2d2", markersize = 8)

    mng = plt.get_current_fig_manager()
    mng.window.state('zoomed')

    plt.show()

    return

@atexit.register
def exit():
    file = open("trackers.txt","w")
    for i in range(len(trackers)):
        for b in range(len(trackers[i])):
            file.write(str(trackers[i][b]) + ",")
        file.write("\n")
    print("Trackers Saved")

if __name__ == "__main__":
    main()

If you want to run it, you'll need the accompanying file "trackers.txt" which saves all the habit data between program runs, here is a direct copy of my file. Just copy and paste this to avoid read errors. Make sure to add a blank line at the end of this file!

0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,

Thank you in advance!

Answer 1

I think the x-axis is not where you think it is. In this line you set the y ticks:

plt.yticks([i for i in range(len(trackers))],tuple(activities))

range starts at 0, so your first activity label is labeling y=0. That is, the line that says "retainer" is the x-axis.

If you want your first label to be at height 1, then you should add one to your ticks:

plt.yticks([i+1 for i in range(len(trackers))],tuple(activities))

Or, more simply:

plt.yticks(range(1, len(trackers)+1), activities)

(As an aside, you have many inefficiencies and awkward constructions in your code. You don't need to call tuple on everything. You are probably better off iterating over things a la for item in trackers instead of for i in range(len(trackers)) .)