eliminating empty elements in a list with python

Question

i have a list as shown below and i'm fairly new to python language . i want to eliminate those five empty elements in my list ( one is the first element (before '0' and four of them is after the last element ('1')) could you please how could i do this ? Thanx

['', '0.', '10.E-03', '12.5E-03', '15.E-03', '18.75E-03', '22.5E-03', '26.25E-03', '30.E-03', '33.75E-03', '37.5E-03', '43.125E-03', '51.5625E-03', '61.5625E-03', '71.5625E-03', '81.5625E-03', '91.5625E-03', '101.563E-03', '111.563E-03', '121.563E-03', '131.563E-03', '141.563E-03', '151.563E-03', '161.563E-03', '171.563E-03', '181.563E-03', '191.563E-03', '201.563E-03', '211.563E-03', '221.563E-03', '231.563E-03', '241.563E-03', '251.563E-03', '261.563E-03', '271.563E-03', '281.563E-03', '291.563E-03', '301.563E-03', '311.563E-03', '321.563E-03', '331.563E-03', '341.563E-03', '351.563E-03', '361.563E-03', '371.563E-03', '381.563E-03', '391.563E-03', '401.563E-03', '411.563E-03', '421.563E-03', '431.563E-03', '441.563E-03', '451.563E-03', '461.563E-03', '471.563E-03', '481.563E-03', '491.563E-03', '501.562E-03', '511.563E-03', '521.563E-03', '531.563E-03', '541.563E-03', '551.563E-03', '561.563E-03', '571.563E-03', '581.563E-03', '591.563E-03', '601.563E-03', '611.563E-03', '621.563E-03', '631.563E-03', '641.563E-03', '651.563E-03', '661.563E-03', '671.563E-03', '681.563E-03', '691.563E-03', '701.563E-03', '711.563E-03', '721.563E-03', '731.563E-03', '741.563E-03', '751.563E-03', '761.563E-03', '771.563E-03', '781.563E-03', '791.563E-03', '801.563E-03', '811.563E-03', '821.563E-03', '831.563E-03', '841.563E-03', '851.563E-03', '861.563E-03', '871.563E-03', '881.563E-03', '891.563E-03', '901.563E-03', '911.563E-03', '921.563E-03', '931.563E-03', '941.563E-03', '951.563E-03', '961.563E-03', '971.563E-03', '981.563E-03', '991.563E-03', '1.', '', '', '', '']

Possible duplicate of [Remove empty strings from a list of strings](http://stackoverflow.com/questions/3845423/remove-empty-strings-from-a-list-of-strings) — Mr. Xcoder, Mar 26 '17 at 14:35

score 4 · Accepted Answer · edited May 23 '17 at 12:25

my_list = ['', '0.', '10.E-03', '12.5E-03', '15.E-03', '18.75E-03', '22.5E-03', '26.25E-03', '30.E-03', '33.75E-03', '37.5E-03', '43.125E-03', '51.5625E-03', '61.5625E-03', '71.5625E-03', '81.5625E-03', '91.5625E-03', '101.563E-03', '111.563E-03', '121.563E-03', '131.563E-03', '141.563E-03', '151.563E-03', '161.563E-03', '171.563E-03', '181.563E-03', '191.563E-03', '201.563E-03', '211.563E-03', '221.563E-03', '231.563E-03', '241.563E-03', '251.563E-03', '261.563E-03', '271.563E-03', '281.563E-03', '291.563E-03', '301.563E-03', '311.563E-03', '321.563E-03', '331.563E-03', '341.563E-03', '351.563E-03', '361.563E-03', '371.563E-03', '381.563E-03', '391.563E-03', '401.563E-03', '411.563E-03', '421.563E-03', '431.563E-03', '441.563E-03', '451.563E-03', '461.563E-03', '471.563E-03', '481.563E-03', '491.563E-03', '501.562E-03', '511.563E-03', '521.563E-03', '531.563E-03', '541.563E-03', '551.563E-03', '561.563E-03', '571.563E-03', '581.563E-03', '591.563E-03', '601.563E-03', '611.563E-03', '621.563E-03', '631.563E-03', '641.563E-03', '651.563E-03', '661.563E-03', '671.563E-03', '681.563E-03', '691.563E-03', '701.563E-03', '711.563E-03', '721.563E-03', '731.563E-03', '741.563E-03', '751.563E-03', '761.563E-03', '771.563E-03', '781.563E-03', '791.563E-03', '801.563E-03', '811.563E-03', '821.563E-03', '831.563E-03', '841.563E-03', '851.563E-03', '861.563E-03', '871.563E-03', '881.563E-03', '891.563E-03', '901.563E-03', '911.563E-03', '921.563E-03', '931.563E-03', '941.563E-03', '951.563E-03', '961.563E-03', '971.563E-03', '981.563E-03', '991.563E-03', '1.', '', '', '', '']

You could also use:

my_list = [element for element in my_list if element]

# You could also use my_list = [element for element in my_list if not element == ''] 
# but checking for 'if element' works

Or, use filter as shown here:

my_list = list(filter(None, my_list))

Thank you , i got it and it works fine . i really appreciate for other replays of Tom Fuller and shizhz . — Nima Geran, Mar 26 '17 at 13:30

score 2 · Answer 2 · edited Jun 20 '20 at 09:12

There are a lot of ways you can accomplish that. To illustrate the topic better, I've benchmarked all the methods, for you to see how efficient each of those are. I strongly recommend using methods 1 and 2. Here are the examples, ordered by their execution time:

1. Filtering the list (recommended)

myList = list(filter(None, myList))

Average execution time (measured with timeit()): 0.037 - 0.045 s

2. List Comprehension

myList = [x for x in myList if x]

Average execution time: 0.055 - 0.065 s

3. Removing `''` n times, were n is the number of `''` in the list

c = myList.count('')
for i in range(c):
    myList.remove('')

Average execution time: 0.088 - 0.1 s

Note: This is not the best way, you should use the recommended method

4. Removing `''` while possible

Note: this method is inspired by this answer and isn't really the best way to do this

while True:
    try: myList.remove('')
    except ValueError: break

Average execution time: 0.097 - 0.11 s

shizhz · Answer 3 · 2017-03-26T14:09:07.333

0

You can either use list comprehension:

[x  for x in original_list if x != ''] # To only remove empty string

Or filter:

filter(lambda x: x != '', original_list) # To only remove empty string

edited Mar 26 '17 at 14:09

answered Mar 26 '17 at 13:19

shizhz

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You don't need a lambda, Read the documentation for [**`filter`**](https://docs.python.org/2/library/functions.html#filter) – Peter Wood Mar 26 '17 at 13:21
With strings, `if x != ''` is the same as `if x`, as `''` is `False`-y – Peter Wood Mar 26 '17 at 13:22
Just make sure to only remove `''` but no other `falsy` value – shizhz Mar 26 '17 at 13:25
What else could be `False`-y in a list of strings? – Peter Wood Mar 26 '17 at 13:31
@shizhz besides for an empty string, `if x` cannot evaluate other falsy value. – Mr. Xcoder Mar 26 '17 at 13:32

eliminating empty elements in a list with python

3 Answers3

1. Filtering the list (recommended)

2. List Comprehension

3. Removing '' n times, were n is the number of '' in the list

4. Removing '' while possible

3. Removing `''` n times, were n is the number of `''` in the list

4. Removing `''` while possible