Two ways to open a file
f = open("data.txt","r") #Setting the file object
f.close() #Close file
#For convenience, and to avoid forgetting to close the file object, you can use the following instead
with open('data.txt',"r") as f: #Setting the file object
str = f.read()
Some simple operations on documents
1.Read files
f = open("data.txt","r") #Setting the file object
str = f.read() #Read all the contents of the txt file into the string str
f.close() #Close the file
2.Read the entire file by line
#The first method
f = open("data.txt","r") #Setting the file object
line = f.readline()
line = line[:-1]
while line: #Until the file is read
line = f.readline() #Read a line of file, including line breaks
line = line[:-1] #Remove line breaks, or not
f.close() #Close file
#The second method
data = []
for line in open("data.txt","r"): #Set the file object and read each line of the file
data.append(line) #Add each line of the file to the list
#The third method
f = open("data.txt","r") #Setting the file object
data = f.readlines() #Read the file directly into the list by line, with the same effect as method 2
f.close() #Close file
3.Write file
Simply write a string to txt
with open('data.txt','w') as f: #Setting the file object
f.write(str) #Writing a string to a file
4.List write file
data = ['a','b','c']
#Single-level list write file
with open("data.txt","w") as f:
f.writelines(data)
Adding new content to the dictionary is done by adding new key/value pairs, modifying or deleting existing key/value pairs as shown in the following examples: #!/usr/bin/python dict = {'Name': 'Zara', 'Age': 7, 'Class': 'First'}
Python method for getting the current path. import os,sys Use sys.path[0], sys.argv[0], os.getcwd(), os.path.abspath(__file__), os.path.realpath(__file__)
When it comes to threads, your brain should have the impression that we can control when it starts but not when it ends, so how do you get the return value of a thread? Today we will share some of our own practices.
Comma-Separated Values (CSV, sometimes called character-separated values because the separating characters can also be other than commas), whose files store tabular data (numbers and text) in plain text
Example: The output is the following case H e l l o W o r l d This can be done using a for loop. for name in "Hello World": print(name) This can also be done using the join method print("\n".join("Hello World"))
In Python 3.0 onwards, keyboard input uses the input function >>> x=input >>> 123 123 There is no display on the command line, and the input 123 is directly assigned to x and printed. Using input alone can't solve most of the data processing, usually
The dict object in Python is a primitive Python data type, stored as a key-value pair, whose Chinese name translates to dictionary, and as the name implies, it is highly efficient at finding the corresponding value by key name
python can replace JavaScript; Pyjamas can be used to achieve Python instead of JavaScript, Pyjamas is a Python ajax development framework that can be used instead of HTML and JavaScript to write web applications , you can reuse and import classes and mod
Colorize old photos with NoGAN's image enhancement technique.NoGAN is a new type of GAN that takes the least amount of time for GAN training.
A very common dictionary task is if we have a dictionary and want to flip its keys and values, the keys will become the values and the values will become the keys