How to pass a list by reference?

Lists are already passed by reference, in that all Python names are references, and list objects are mutable. Use slice assignment instead of normal assignment.

def add(L1, L2, L3):
    L3[:] = L1 + L2

However, this isn’t a good way to write a function. You should simply return the combined list.

def add(L1, L2):
    return L1 + L2

L3 = add(L1, L2)

Related Posts:

  1. How do I pass a variable by reference?
  2. Purpose of “%matplotlib inline”
  3. How do I update Anaconda?
  4. TypeError: ‘str’ object is not callable (Python)
  5. Dijkstra’s algorithm in python
  6. How to create a GUID/UUID in Python
  7. Replace ‘ with \’ in a string
  8. How can I install pip on Windows?
  9. Best way to convert string to bytes in Python 3?
  10. Does Python have a string ‘contains’ substring method?
  11. Difference between import numpy and import numpy as np
  12. No module named ‘sklearn.cross_validation’
  13. Maximum and Minimum values for ints
  14. Arrays used as indices must be of integer (or boolean) type
  15. Are static class variables possible in Python?
  16. Why am I getting “LinAlgError: Singular matrix” from grangercausalitytests?
  17. ‘method’ object is not subscriptable. Don’t know what’s wrong
  18. How do I copy a file in Python?
  19. EOFError: Ran out of input
  20. Get Color Palettes from ColorHunt.co in Python
  21. What does the Pydoc module do?
  22. size of NumPy array
  23. Best way to strip punctuation from a string
  24. How can I explicitly free memory in Python?
  25. filename.whl is not supported wheel on this platform
  26. What is the meaning of [:] in python [duplicate]
  27. Finding and replacing elements in a list
  28. socket.error: [Errno 48] Address already in use
  29. No module named MySQLdb
  30. How to determine a Python variable’s type?
  31. Could not find a version that satisfies the requirement
  32. Removing Conda environment
  33. Cannot convert list to array: ValueError: only one element tensors can be converted to Python scalars
  34. How do I plot only a table in Matplotlib?
  35. Change column type in pandas
  36. Split by comma and strip whitespace in Python
  37. How to remove punctuation marks from a string in Python 3.x using .translate()?
  38. Calculating Covariance with Python and Numpy
  39. What is the easiest way to remove all packages installed by pip?
  40. In practice, what are the main uses for the new “yield from” syntax in Python 3.3?
  41. Subplot for seaborn boxplot
  42. Dump a NumPy array into a csv file
  43. How to delete a character from a string using Python
  44. installing urllib in Python3.6
  45. What is sys.maxint in Python 3?
  46. How do you get the magnitude of a vector in Numpy?
  47. Finding all possible permutations of a given string in python
  48. Exit while loop in Python
  49. How do I check if a list is empty?
  50. IndexError: list index out of range and python
  51. Don’t understand why UnboundLocalError occurs (closure) [duplicate]
  52. OSError – Errno 13 Permission denied
  53. ImportError: No module named ‘Queue’
  54. ImportError: No Module Named bs4 (BeautifulSoup)
  55. How to calculate rolling / moving average using python + NumPy / SciPy?
  56. TypeError: ‘int’ object does not support item assignment
  57. Convert datetime to Unix timestamp and convert it back in python
  58. Defining lists as global variables in Python
  59. How to stop Python closing immediately when executed in Microsoft Windows
  60. Error: “dictionary update sequence element #0 has length 1; 2 is required” on Django 1.4
  61. module has no attribute
  62. How to print number with commas as thousands separators?
  63. double for loops in python
  64. Convert hex string to int in Python
  65. Function to close the window in Tkinter
  66. Is there a way to specify which pytest tests to run from a file?
  67. super() fails with error: TypeError “argument 1 must be type, not classobj” when parent does not inherit from object
  68. Appending values to dictionary in Python
  69. TypeError: argument of type ‘NoneType’ is not iterable
  70. How to remove parentheses from string [duplicate]
  71. BeautifulSoup and lxml.html – what to prefer?
  72. How to clear up screen in pygame?
  73. Efficiently sorting a numpy array in descending order?
  74. How to replace multiple substrings of a string?
  75. built-in range or numpy.arange: which is more efficient?
  76. python-How to solve KeyError: 2?
  77. Move column by name to front of table in pandas
  78. How to search through dictionaries?
  79. Element-wise addition of 2 lists?
  80. Converting integer to binary in python
  81. Open File in Another Directory (Python)
  82. Python: Making a beep noise
  83. Failed building wheel for Twisted in Windows 10 python 3
  84. python flask import error
  85. What do I use for a max-heap implementation in Python?
  86. Is there a math nCr function in python? [duplicate]
  87. ImportError: No module named Cython.Distutils
  88. Python Brute Force algorithm
  89. What’s the correct way to convert bytes to a hex string in Python 3?
  90. How can I install a .egg Python package on Windows (attempt using easy_install not working)
  91. Package libffi was not found in the pkg-config search path REDHAT6.5
  92. Line is too long. Django PEP8
  93. TypeError: zip argument #2 must support iteration
  94. CS231n: How to calculate gradient for Softmax loss function?
  95. How to create a new database using SQLAlchemy?
  96. Python 3 integer division [duplicate]
  97. numpy/scipy/ipython:Failed to interpret file as a pickle
  98. What is the Python equivalent of static variables inside a function?
  99. Python – difference between two strings
  100. Flask-framework: MVC pattern

Leave a Comment