Python3.6 programming skills summary, python3.6 programming skills

Python3.6 programming skills summary, python3.6 programming skills

I have been studying python for more than half a year and found many practical programming skills that are easy to ignore. The following is a summary.

1. Print the file path of the import module

import threadingimport socketprint(threading)print(socket)

Module 'threading' from '/Users/taorui/anaconda3/lib/python3.6/threading. py'
Module 'socket 'from'/Users/taorui/anaconda3/lib/python3.6/socket. py'

2. Operator _ in interactive environment

2+1

3

_

3

print(_)

3

3. Check python objects

test=[1,3,5,7]print(dir(test))

['Add','Class','Contains','Delattr','Delitem','Dir','Doc','Eq','Format','Ge','Getattribute','Getitem','Gt','Hash','Iadd','Imul','Init','Init_subclass','Iter','Le','Len','Lt','Mul','Ne','New','Reduce','Performance_ex','Repr','Reversed','Rmul','Setattr','Setitem','Sizeof','Str','Subclasshook', 'Append', 'clear', 'copy', 'Count', 'extend', 'index', 'insert', 'pop', 'delete ', 'reverse', 'sort ']

4. Check the python version

import sysprint(sys.version)

3.6.3 | Anaconda, Inc. | (default, Oct 6 2017, 12:04:38)
[GCC 4.2.1 Compatible Clang 4.0.1 (tags/RELEASE_401/final)]

5. Combine multiple strings

test=['I','Like','Python','automation']print(test)ss=""print(ss.join( test))

['I', 'like', 'python', 'automation ']
ILikePythonautomation

5. Four string/list flip Methods

testList=[1,3,5]testList.reverse()print(testList)

[5, 3, 1]

Flip in a loop and iterate the output

for element in reversed([1,3,5]):    print(element)

5
3
1

One line of code flip string

"Test Python"[::-1]

'Nohtyp tset'

Use slice flip list

[1,3,5][::-1]

[5, 3, 1]

6. Playback Enumeration

testlist=[10,20,30]for i,value in enumerate(testlist):    print(i,':',value)

0: 10
1: 20
2: 30

7. Use enumeration in python

class Shapes:    Circle,Square,Tringle,Quadrangle=range(4)print(Shapes.Circle)print(Shapes.Square)print(Shapes.Tringle)print(Shapes.Quadrangle)

0
1
2
3

8. Use the * operator to unpack function parameters

def test(x,y,z):    print(x,y,z)testDict={'x':1,'y':2,'z':3}testList=[10,20,30]test(*testDict)test(**testDict)test(*testList)

X y z
1 2 3
10 20 30

9. use dictionaries to store selection operations

stdcalc={    'sum':lambda x,y:x+y,    'subtract':lambda x,y:x-y}print(stacalc['sum'](9,3))print(stacalc['subt'](9,3))

12
6

10. dictionary set Derivation

testSet={i*2 for i in range(10)}testDict={i: i*i for i in range(10) }print(testSet)print(testDict)

{0, 2, 4, 6, 8, 10, 12, 14, 16, 18}
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16, 5: 25, 6: 36, 7: 49, 8: 64, 9: 81}

11. In-situ exchange of two numbers

x,y=10,20print(x,y)x,y=y,xprint(x,y)

10 20
20 10

12. chain-like comparison Operators

n=10result=1<n<20print(result)result=1>n>20print(result)

True
False

13. conditional assignment using ternary Operators

out=[m**2 if m>10 else m**4 for m in range(50)]print(out)

[0, 1, 16, 81,256,625,129 6, 2401,409 6, 6561,100 00, 121,144,169,196,225,256,289,324,361,400,441,484,529,576,625,676,729,784,841,900,961,102 4, 1089,115 6, 1225,129 6, 1369,144 4, 1521,160 0, 1681,176 4, 1849,193 6, 2025,211 6, 2209,230 4, 2401]

14. Store list elements to new variables

testList=[1,2,3]x,y,z=testListprint(x,y,z)

1 2 3

15. One line of code is used to calculate the factorial of any number.

import functoolsresult=(lambda k:functools.reduce(int.__mul__,range(1,k+1),1))(3)print(result)

6

16. Find the number that appears most frequently in the list

test=[1,2,3,4,2,2,3,4,1,4,4,4,4,]print(max(set(test),key=test.count))

4

17. Check the memory usage of an object

import sysx=1print(sys.getsizeof(x))

28

18. Build a dictionary from the connected Sequence

t1=(1,2,3)t2=(10,20,30)print(dict(zip(t1,t2)))

{1: 10, 2: 20, 3: 30}

19. Search for multiple prefix and suffix strings in one line of code

print("http://www.google.com".startswith(("http://","https://")))print("http://www.google.co.uk".endswith((".com",".uk")))

True
True

20. Construct a switch-case statement without loops

import itertoolstest=[[-1,-2],[30,40],[25,35]]print(list(itertools.chain.from_iterable(test)))

[-1,-2, 30, 40, 25, 35]

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