How do I read a specific column in a CSV file in Python?

  April 9, 2020
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How do I read a specific column in a CSV file in Python?

Use pandas. read_csv() to read a specific column from a CSV file. To read a CSV file, call pd. read_csv(file_name, usecols=cols_list) with file_name as the name of the CSV file, delimiter as the delimiter, and cols_list as the list of specific columns to read from the CSV file.

How do I get the header of a CSV file in Python?

Converting the CSV file to a data frame using the Pandas library of Python….Steps :

  1. Open the CSV file using DictReader.
  2. Convert this file into a list.
  3. Convert the first row of the list to the dictionary.
  4. Call the keys() method of the dictionary and convert it into a list.
  5. Display the list.

How do I view the header of a CSV file?

Steps to read a CSV file:

  1. Import the csv library. import csv.
  2. Open the CSV file. The .
  3. Use the csv.reader object to read the CSV file. csvreader = csv.reader(file)
  4. Extract the field names. Create an empty list called header.
  5. Extract the rows/records.
  6. Close the file.

How do I create a .CSV header?

If your CSV file doesn’t have headers, you can add them by simply creating a new first line in the text file and typing in your headers.

How do you read a column from a text file in Python?

You can read a text file using the open() and readlines() methods. To read a text file into a list, use the split() method. This method splits strings into a list at a certain character. In the example above, we split a string into a list based on the position of a comma and a space (“, ”).

How do you read a specific column in a text file in Python?

Using . This can be useful if we want to access specific columns of the file. #Create a variable for the file name filename = “Plates_output_simple. csv” #Open the file infile = open(filename, ‘r’) lines = infile. readlines() for line in lines: sline = line.

How do I read a CSV file without header in Python?

Steps to read CSV columns into a list without headers:

  1. Import the csv module.
  2. Create a reader object (iterator) by passing file object in csv.
  3. Call the next() function on this iterator object, which returns the first row of CSV.
  4. Store the headers in a separate variable.

How do you read column names in Python?

To access the names of a Pandas dataframe, we can the method columns(). For example, if our dataframe is called df we just type print(df. columns) to get all the columns of the Pandas dataframe. After this, we can work with the columns to access certain columns, rename a column, and so on.

How do you read a CSV file in a list in Python?

How to read a csv file into a list in Python

  1. file = open(“sample.csv”, “r”)
  2. csv_reader = csv. reader(file)
  3. lists_from_csv = []
  4. for row in csv_reader:
  5. lists_from_csv. append(row)
  6. print(lists_from_csv) Each row is a separate list.

How do I add a column to a CSV file in Python?

How to add a column to a CSV file in Python

  1. df = pd. read_csv(“sample.csv”)
  2. df[“new_column”] = “”
  3. df. to_csv(“sample.csv”, index=False)

How do I read a line from a file in Python?

How to read specific lines of a text file in Python

  1. a_file = open(“test_file.txt”)
  2. lines_to_read = [0, 2]
  3. for position, line in enumerate(a_file): Iterate over each line and its index.
  4. if position in lines_to_read:
  5. print(line)

How to read a CSV file in Python?

Here, we have the read_csv () function which helps to read the CSV file by simply creating its object. The column name can be written inside this object to access a particular column, the same as we do in accessing the elements of the array.

How do I read a specific column from a CSV file?

Read and Print Specific Columns from The CSV Using csv.reader Method In the following example, it will print the column COUNTRY_NAME, by specifying the column number as 1 (lines). The CSV file is containing three columns, and the column number starts with 0 when we read CSV using csv.reader method.

How many columns are there in a CSV file?

The CSV file is containing three columns, and the column number starts with 0 when we read CSV using csv.reader method. 3. Read CSV via csv.DictReader Method and Print Specific Columns

How to skip the first line of a CSV file?

Note: To skip the first line (header row), you can use next (csv_reader) command before the FOR LOOP. 2. Read and Print Specific Columns from The CSV Using csv.reader Method In the following example, it will print the column COUNTRY_NAME, by specifying the column number as 1 ( lines [1] ).