python note 4

1, implementation transpose matrix:

#矩阵的转置
jz=[[1,2,3],[4,5,6],[7,8,9]]
print(jz)
for i,row in enumerate(jz):
    for j,col in enumerate(row):
        if i<j:
            jz[i][j],jz[j][i]=jz[j][i],jz[i][j]
print(jz)

 #enumerate usage:

Syntax: the enumerate ( Sequence , [ Start = 0 ])

• sequence - a sequence, an iterator, or other objects to support iteration.
• start - start index position.

Example:

>>>seasons = ['Spring', 'Summer', 'Fall', 'Winter']

>>> list(enumerate(seasons)) [(0, 'Spring'), (1, 'Summer'), (2, 'Fall'), (3, 'Winter')]

>>> List ( the enumerate ( Seasons , Start = 1 ) ) # 1 starts from index

[(1, 'Spring'), (2, 'Summer'), (3, 'Fall'), (4, 'Winter')]

Another method to achieve:

#矩阵的转置
jz=[[1,2,3],[4,5,6],[7,8,9]]
print(jz)
for i in range(len(jz)):
    for j in range(i):
            jz[i][j],jz[j][i]=jz[j][i],jz[i][j]
print(jz)

Irregular matrix transpose implementation:

# Irregular length transposed matrix 
JZ = [[l, 2,3], [4,5,6 ]]
 Print (JZ) 
T = []
 for Row in JZ:
     for I, COL in the enumerate (Row):
         IF len (t) <I +. 1:   # JZ odd row number will add t 
            t.append ([]) 
        t [I] .append (COL) 
Print (t)

2, 10 randomly generated numbers (less than 21), there are several statistical duplicate numbers, namely what; statistically repeated a few figures, what are:

Import Random 
the nums = []
 for _ in Range (10 ): 
    nums.append (random.randrange ( 21 is ))
 Print (the nums) 
S, D = [], [] # are used to hold the same few figures and different few figures 
lenth = len (the nums) 
State = [0] * lenth   # used for marking, and marking the location of duplicate numbers 

for I in Range (lenth): # a first layer of elements for each cycle traversal 
    flag = False    # each element must be compared before to re-flag initial value 
    IF State [i] == 1:   # If the i-th element has been repeated, then do not compare, depending on the back of the state [j ] = 1 and State [I] = 1 
        Continue 
    forJ in Range (i +. 1, lenth):   # For each element i in element i to be behind position compared 
        IF State [J] ==. 1 :  
             Continue 
        IF the nums [i] == the nums [J]: 
            flag = True   # repeated, assigned to the flag is True, and this position is marked state. 1 
            state [J] =. 1   IF flag: 
        s.append (the nums [I]) 
        state [I] =. 1
     the else : 
        d.append ( the nums [I]) Print ( " Same has the Array = {{0}}. 1 " .format (S, len (S)))
 Print ( " Different has the Array = {{0}}. 1 " .format (D, len (D)))
    

result:

[14, 3, 9, 12, 7, 9, 11, 17, 11, 17]
same Array=[9, 11, 17] has 3
different Array=[14, 3, 12, 7] has 4