import tkinter as tk
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg

def plot_function(func_str, num_points, step, multiplier, x_func):
    try:
        x_values = np.linspace(x_func[0], x_func[1], num_points)
        func = lambda x: eval(func_str)
        y_values = func(x_values * multiplier)

        ax.clear()
        ax.plot(x_values, y_values, label=f'{func_str} ({x_func[0]} to {x_func[1]})')
        ax.legend()
        canvas.draw()
    except Exception as e:
        print(f"Error: {e}")

def on_update():
    try:
        func_str = entry_function.get()
        num_points = int(entry_num_points.get())
        step = float(entry_step.get())
        multiplier = float(entry_multiplier.get())
        x_func = [float(entry_x_start.get()), float(entry_x_end.get())]

        plot_function(func_str, num_points, step, multiplier, x_func)
    except ValueError:
        pass

# 创建主窗口
root = tk.Tk()
root.title("Function Plotter")

# 创建图形区域
fig, ax = plt.subplots(figsize=(5, 4))
canvas = FigureCanvasTkAgg(fig, master=root)
canvas_widget = canvas.get_tk_widget()
canvas_widget.grid(row=0, column=1, rowspan=10)

# 添加控件
tk.Label(root, text="Function:").grid(row=0, column=0)
entry_function = tk.Entry(root)
entry_function.grid(row=0, column=1)
entry_function.insert(0, "np.sin(x)")

tk.Label(root, text="Number of Points:").grid(row=1, column=0)
entry_num_points = tk.Entry(root)
entry_num_points.grid(row=1, column=1)
entry_num_points.insert(0, "100")

tk.Label(root, text="Step Size:").grid(row=2, column=0)
entry_step = tk.Entry(root)
entry_step.grid(row=2, column=1)
entry_step.insert(0, "0.1")

tk.Label(root, text="Multiplier:").grid(row=3, column=0)
entry_multiplier = tk.Entry(root)
entry_multiplier.grid(row=3, column=1)
entry_multiplier.insert(0, "1.0")

tk.Label(root, text="X Start:").grid(row=4, column=0)
entry_x_start = tk.Entry(root)
entry_x_start.grid(row=4, column=1)
entry_x_start.insert(0, "-10.0")

tk.Label(root, text="X End:").grid(row=5, column=0)
entry_x_end = tk.Entry(root)
entry_x_end.grid(row=5, column=1)
entry_x_end.insert(0, "10.0")

update_button = tk.Button(root, text="Update Plot", command=on_update)
update_button.grid(row=6, column=0, columnspan=2)

# 初始绘制
on_update()

# 运行主循环
root.mainloop()