我遇到了两种计算lcm的方法。第一种方法使用递归，而第二种方法使用from tkinter import *
from tkinter import filedialog
from tkinter import messagebox
def forButton1():
if MyVar1.get()==1:
filename1 = filedialog.askopenfilename(initialdir="C:/DSSAT47/Soil")
with open(filename1) as f1:
for i in f1:
myList1.insert(END, i)
print(filename1)
def forButton2():
if MyVar2.get() == 1:
filename2 = filedialog.askopenfilename(initialdir="C:/DSSAT47/Weather")
with open(filename2) as f2:
for i in f2:
myList1.insert(END, i)
print(filename2)
def forClear1():
MyVar1.set(0)
print("*****x file removed*****")
def forClear2():
MyVar2.set(0)
print("*****y file removed*****")
def forReset():
myList1.delete(0, 'end')
MyVar1.set(0)
MyVar2.set(0)
print("*****All files removed*****")
print("Select new files:")
def forSubmit():
if MyVar1.get()== 0 or MyVar2.get()==0:
messagebox.showwarning("Warning", "Select input files!")
def forButton7():
if MyVar1.get()==0 and MyVar2.get()==0:
messagebox.showwarning("Warning", "Select input files!")
else:
filename3 = filedialog.askopenfilename(initialdir="F:/ISRO/Python codes")
with open(filename3) as f3:
for i in f3:
myList.insert(END, i)
print(filename3)
def forExit():
root.destroy()
root = Tk()
root.title("Spatialization of DSSAT")
root.grid_columnconfigure(0, weight=1)
topFrame = LabelFrame(root, text="Select input file")
topFrame.grid(row=0, column=0, padx=8, pady=8, sticky=N+E+S+W)
topFrame.grid_rowconfigure(0, weight=1)
topFrame.grid_rowconfigure(1, weight=1)
topFrame.grid_columnconfigure(0, weight=1)
topFrame.grid_columnconfigure(1, weight=1)
topFrame.grid_columnconfigure(2, weight=1)
middleFrame = LabelFrame(root, text="Input data")
middleFrame.grid(row=1, column=0, padx=8, pady=8, sticky=N+E+S+W)
middleFrame.grid_rowconfigure(0, weight=1)
middleFrame.grid_rowconfigure(1, weight=0)
middleFrame.grid_columnconfigure(0, weight=1)
middleFrame.grid_columnconfigure(1, weight=1)
bottomFrame = LabelFrame(root, text="Model Output")
bottomFrame.grid(row=2, column=0, padx=8, pady=8, sticky=N+E+S+W)
bottomFrame.grid_rowconfigure(0, weight=1)
bottomFrame.grid_columnconfigure(0, weight=1)
MyVar1 = IntVar()
MyVar2 = IntVar()
MyCheckbutton1 = Checkbutton(topFrame, text="x", variable=MyVar1)
MyCheckbutton1.grid(row=0, column=0, padx=4, pady=4)
Button1 = Button(topFrame, text="Choose xFile", command=forButton1)
Button1.grid(row=0, column=1, padx=4, pady=4)
#Button3 = Button(topFrame, text="Clear", command=forClear1)
#Button3.grid(row=0, column=2, padx=4, pady=4)
MyCheckbutton2 = Checkbutton(topFrame, text="y", variable=MyVar2)
MyCheckbutton2.grid(row=1, column=0, padx=4, pady=4)
Button2 = Button(topFrame, text="Choose yFile", command=forButton2)
Button2.grid(row=1, column=1, padx=4, pady=4)
#Button4 = Button(topFrame, text="Clear", command=forClear2)
#Button4.grid(row=1, column=2, padx=4, pady=4)
innerMiddleFrame = Frame(middleFrame)
innerMiddleFrame.grid(row=0, column=0, columnspan=2, padx=4, pady=4)
innerMiddleFrame.grid_columnconfigure(0, weight=1)
innerMiddleFrame.grid_columnconfigure(1, weight=0)
scrollbar = Scrollbar(innerMiddleFrame)
myList1 = Listbox(innerMiddleFrame, yscrollcommand=scrollbar.set)
myList1.grid(row=0, column=0, sticky=N+E+S+W)
scrollbar.config(command=myList1.yview)
scrollbar.grid(row=0, column=1, sticky=N+E+S+W)
Button5 = Button(middleFrame, text="Reset", command=forReset)
Button5.grid(row=1, column=0, padx=4, pady=4)
#Button6 = Button(middleFrame, text="Submit", command=forSubmit)
#Button6.grid(row=1, column=1, padx=4, pady=4)
innerBottomFrame = Frame(bottomFrame)
innerBottomFrame.grid(row=0, column=0, columnspan=2, padx=4, pady=4)
innerBottomFrame.grid_columnconfigure(0, weight=1)
innerBottomFrame.grid_columnconfigure(1, weight=0)
scrollbar = Scrollbar(innerBottomFrame)
myList = Listbox(innerBottomFrame, yscrollcommand=scrollbar.set)
myList.grid(row=0, column=0, sticky=N+E+S+W)
scrollbar.config(command=myList.yview)
scrollbar.grid(row=0, column=1, sticky=N+E+S+W)
Button7 = Button(bottomFrame, text="Select Output File", command=forButton7)
Button7.grid(row=1, column=0, padx=4, pady=4)
Button8 = Button(bottomFrame, text="Exit", command=forExit)
Button8.grid(row=1, column=1, padx=4, pady=4)
root.geometry("400x590")
import geopandas as gpd
#from geopandas.io.file import read_file
fp = r"F:\ISRO\Spatial_Data\grid_jagalur_spatialjoin.shp"
data = gpd.read_file(fp)
print (type(data))
data.head()
data.plot()
import matplotlib.pyplot as plt
plt.show()
root.mainloop()
运算符。我什至观察到，如果存在深度递归，则第一种方法会引发错误。除了在方法2中使用插入符号之外，我认为还必须有一种模式或一些直观的逻辑。如果是这样，您能给我解释一下吗？
caretdef gcd(a,b):
if (a == b):
return a
if (a > b):
return gcd(a-b, b)
return gcd(a, b-a)
def lcm(a,b):
return (a*b) / gcd(a,b)
答案 0 :(得分：1)
使用3个XOR操作只是交换两个变量的愚蠢方式。
a ^= b
b ^= a
a ^= b
与
相同a,b = b,a
这两种方法使用不同的计算方法，但是通过计算较大数除以较小数的余数，两者都以相同的方式收敛。递归方法使用多次减法以获得模的等价物，而迭代方法直接使用模运算符。递归方法将执行更多的迭代，因此对于相距很远的数字效率会大大降低。
将模运算符与递归方法结合使用将使两个函数成为单行定义：
def gcd(a,b): return a if b == 0 else gcd(b,a%b)
def lcm(a,b): return (a*b)//gcd(a,b)
顺便说一下，这些是用于计算GCD的欧几里得算法的实现：https://en.wikipedia.org/wiki/Euclidean_algorithm