问题描述
有人可以帮我将 for 循环 替换为 while 循环 我正在努力弄清楚吗?
这个问题特别要求我们不要使用 for 循环。这就是为什么我需要用 while 循环
替换它我在下面列出了:
def matrix_equal(matrix1,matrix2):
"""
-------------------------------------------------------
Compares two matrices to see if they are equal - i.e. have the
same contents in the same locations.
Use: equal = matrix_equal(matrix1,matrix2)
-------------------------------------------------------
Parameters:
matrix1 - the first matrix (2D list of ?)
matrix2 - the second matrix (2D list of ?)
Returns:
equal - True if matrix1 and matrix2 are equal,False otherwise (boolean)
------------------------------------------------------
"""
equal = True
if((len(matrix1) != len(matrix2)) or (len(matrix1[0]) != len(matrix2[0]))):
equal = False
for x in range(len(matrix1)):
if(equal == False):
break
for y in range(len(matrix1[0])):
num1 = matrix1[x][y]
num2 = matrix2[x][y]
if(num1 != num2):
equal = False
break
return equal
样品测试:
First matrix:
0 1 2
0 c a t
1 d o g
2 b i g
Second matrix:
0 1 2
0 c a t
1 d o g
2 b i g
Equal matrices: True
我们必须遵守的条件:
1. should not call input in the function
2. should not call print in the function
3. should not have multiple returns
解决方法
这应该可以解决您的问题,这是使用 while 循环的解决方案:
cache=True
,
改变
for x in range(len(matrix1)):
到
x = 0
while x < len(matrix1):
x += 1
干杯!
,你可以变换:
for i in range(mat.shape[0]):
{do stuff...}
进入
i = 0
while i < mat.shape[0]:
{do stuff...}
# increment i with 1
i += 1
所以在这里你会得到:
def mat_eq_while(matrix1,matrix2):
i = 0
j = 0
equal = True
if(not (mat1.shape == mat2.shape) ):
equal = False
while i < mat1.shape[0]:
if(equal == False):
break
while j < mat1.shape[1]:
num1 = matrix1[i,j]
num2 = matrix2[i,j]
if(num1 != num2):
equal = False
break
j += 1
i += 1
return equal
测试一下
import numpy as np
mat1 = np.matrix(range(9)).reshape(3,3)
mat2 = np.matrix(range(1,10)).reshape(3,3)
print( mat_eq_while(mat1,mat1) )
print( mat_eq_while(mat1,mat2) )