TKinter Slider widget

[Jemeronimo]

Hey guys! For school I'm making a program in Tkinter with some Sliders. My code is far from nice but I'm doing this all by myself so don't be too hard on me please ^^

I want to add ticks to my slider. Basically I want it to say 0 all on the left and x_o all on the right. Can someone help me doing this? I've been looking around on the internet for a while but can't find it.

Any other tips are very welcome as well.

# Import everything
import numpy as np
import math as math
import matplotlib
import tkinter as Tk
import matplotlib.pyplot as plt
from matplotlib.widgets import Slider, Button
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg

# Set up for the App
pi = math.pi
matplotlib.use('TkAgg')
root = Tk.Tk()
root.wm_title("Name of file")
fig = plt.Figure()
canvas = FigureCanvasTkAgg(fig, root)
canvas.get_tk_widget().pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

# Make subplots
ax1 = fig.add_subplot(221)
ax2 = fig.add_subplot(222)
ax3 = fig.add_subplot(223)
ax4 = fig.add_subplot(224)
fig.subplots_adjust(bottom=0.2, hspace=0.75)
x = np.linspace(0, 100, 1000)
x2 = np.linspace(0, 3*pi, 1000)
font = {'family': 'serif',
        'color':  'darkred',
        'weight': 'normal',
        'size': 10,
        }


def func1(t, omega, position):
    return (position-0.5) * np.cos(math.pi*t/40+omega+pi/2)+0.5


def func(sr, k, l):
    return 2*sr*np.cos(k*l*10)


# Set up axes
ax1.plot(x, func1(x, 0, 0.75), 'k', label="func1")
ax1.plot(x, func1(x, pi, 0.75), 'r', label="func2")
ax1.legend(loc="upper left", bbox_to_anchor=(0.8, 1))
ax1.axis([6*pi, 20*pi, 0, 1])
ax1.set_title("Behavior of a standard D.C.", fontdict=font, fontsize='12')
ax1.set_xlabel("k", fontdict=font)
ax1.set_ylabel("Splitting ratio", fontdict=font)

ax2.plot(x, func(1, x, 0.1)*func1(x, 0, 0.75), 'k')
ax2.plot(x, func(1, x, 0.11)*func1(x, pi, 0.75), 'r')
ax2.axis([6*pi, 20*pi, -1.5, 1.5])
ax2.set_title("Cosine wave functions", fontdict=font, fontsize='12')
ax2.set_xlabel("$k$", fontdict=font)
ax2.set_ylabel("$\psi$(k)", fontdict=font)

ax3.plot(x, func(0.5, x, 0.1), 'k')
ax3.set_title("Intensity", fontdict=font, fontsize='12')
ax3.set_xlabel("Wavenumber k", fontdict=font)
ax3.set_ylabel("Intensity", fontdict=font)
ax3.axis([6*pi, 20*pi, -1.5, 1.5])

ax4.plot(x, np.fft.fft(func(0.5, x, 0.1)), "k")
ax4.axis([-5, max(x)+5, -5, 500])
ax4.set_title("Fourier transform", fontdict=font, fontsize='12')
ax4.set_xlabel("Depth (z)", fontdict=font)
ax4.set_ylabel("Reflectivity", fontdict=font)

# Make Sliders
s1_value = fig.add_axes([0.125, 0.52, 0.35, 0.02])
s_1 = Slider(s1_value, '\nSplitting Ratio\n (SR)', 0.25, 0.75,  valfmt='%0.2f', valinit=0.75)
s2_value = fig.add_axes([0.125, 0.1, 0.35, 0.02])
s_2 = Slider(s2_value, '$\Delta$ L', 0.1, 2*pi, valinit=0.1)


def update(val):
    # Clear all and set again
    ax1.clear()
    ax2.clear()
    ax3.clear()
    ax4.clear()

    pos_s1 = s_1.val
    pos_s2 = s_2.val
    ax1.plot(x, func1(x, 0, pos_s1), label="func1")
    ax1.plot(x, func1(x, pi, pos_s1), label="func2")
    ax1.legend(loc="upper left", bbox_to_anchor=(0.8, 1))
    ax1.set_title("Behavior of a standard D.C.")
    ax1.set_xlabel("k")
    ax1.set_ylabel("Splitting ratio")
    ax1.axis([6 * pi, 20 * pi, 0, 1])

    ax2.plot(x, func(1, x, 0.1) * func1(x, 0, pos_s1))
    ax2.plot(x, func(1, x, 0.1) * func1(x, pi, pos_s1))
    ax2.set_title("Cosine wave functions")
    ax2.set_xlabel("k")
    ax2.set_ylabel("$\psi$(k)")
    ax2.axis([6 * pi, 20 * pi, -1.5, 1.5])

    ax3.plot(x, func(0.5, x, pos_s2))
    ax3.set_title("Intensity")
    ax3.set_xlabel("Wavenumber k")
    ax3.set_ylabel("Intensity")
    ax3.axis([6 * pi, 20 * pi, -1.5, 1.5])

    ax4.plot(x, np.fft.fft(func(1, x, pos_s2) * func1(x, 0, pos_s1)))
    ax4.set_title("Fourier transform ")
    ax4.set_xlabel("Depth (z)")
    ax4.set_ylabel("Reflectivity")
    ax4.axis([-5, max(x)+5, -2, 500])


resetax = fig.add_axes([0.8, 0.025, 0.1, 0.04])
button = Button(resetax, 'Reset', hovercolor='0.975')


def reset(event):
    s_1.reset()
    s_2.reset()


button.on_clicked(reset)
s_1.on_changed(update)
s_2.on_changed(update)


Tk.mainloop()

[Larz60+]

see this: https://www.python-course.eu/tkinter_sliders.php
You can use text 'ticks' (hyphens for vertical scale, "'" for horizontal scale) if you don't like numbers