a = {0:[[1,2,3], [1,3,4,5]]}
print([1,2,3] in a.values())
I get False. Because this list is in values I need True. Is it possible to check all lists in nested list as a value in dictionary? Maybe without loops?
Since you're using python3 you can do this:
[1,2,3] in list(a.values())[0]
a.values() returns a dictionary view. dictionary views
Then you can wrap the dictionary view into list but this list will contain only one element which can be accessed by index 0. However, if your dictionary contains several keys and corresponding values then list(a.values()) will contain the same number of elements (values mapped to keys) as keys in the dictionary.
Note that when you use some_value in some_collection construct and don't use loops explicitly it will still iterate through the collection.
Related
bigList = [list1,list2,list3]
I need a way to get the name of list1 using the zero index
bigList[0] just gives you all the items in the list
My original code prints all the items in the lists while the modified one says the index is out of range. I want it to give me the ilness names not all the symptoms.
Original code
https://i.stack.imgur.com/HDlA9.png
Modified
https://i.stack.imgur.com/5Qdh2.png
I'm extracting data from JSON and mapping two arrays in presto.It works fine when there are no repeated values in the array but fails with error - Duplicate map keys are not allowed if any of the values are repeated.I need those values and cannot remove any of the values from the array.Is there a work around for this scenario?
Sample values:
array1 -- [Rewards,NEW,Rewards,NEW]
array2 -- [losg1,losg2,losg3,losg4]
Map key/value has to be generated like this [Rewards=>losg1,NEW=>losg2,Rewards=>losg3,NEW=>losg4]
Pairs of associations can be returned like this:
SELECT ARRAY[ROW('Rewards', 'losg1'), ROW('NEW', 'losg2'), ROW('Rewards', 'losg3')]
I'm new to python, and I'm trying to check if a String is inside a list.
I have these two variables:
new_filename: 'SOLICITUDES2_20201206.DAT' (str type)
and
downloaded_files:
[['SOLICITUDES-20201207.TXT'], ['SOLICITUDES-20201015.TXT'], ['SOLICITUDES2_20201206.DAT']] (list type)
for checking if the string is inside the list, I'm using the following:
if new_filename in downloaded_files:
print(new_filename,'downloaded')
and I never get inside the if.
But if I do the same, but with hard-coded text, it works:
if ['SOLICITUDES2_20201206.DAT'] in downloaded_files_list:
print(new_filename,'downloaded')
What am I doing wrong?
Thanks!
Your downloaded_files is a list of lists. A list can contain anything insider it, numbers, list, dictionaries, strings and etc. If you are trying to find if your string is inside the list, the if statement will only look for identical matches, i.e., strings.
What I suggest you do is get all the strings into a list instead of a list of lists. You can do it using list comprehension:
downloaded_files = [['SOLICITUDES-20201207.TXT'], ['SOLICITUDES-20201015.TXT'], ['SOLICITUDES2_20201206.DAT']]
downloaded_files_list = [file[0] for file in downloaded_files]
Then, your if statement should work:
new_filename = 'SOLICITUDES2_20201206.DAT'
if new_filename in downloaded_files_list:
print(new_filename,'downloaded')
Your code is asking if a string is in a list of lists of a single string each, which is why it doesn't find any.
I have a list(rs_data) with sublists obtained from a Dataframe, and some rows from Dataframe contain multiple elements, like those:
print(rs_data)
rs1791690, rs1815739, rs2275998
rs6552828
rs1789891
rs1800849, rs2016520, rs2010963, rs4253778
rs1042713, rs1042714, rs4994, rs1801253
I want to obtain a list in which each element (rs….) is separated, something like this:
{'rs1791690', 'rs1815739', 'rs227599', 'rs401681', 'rs2180062', 'rs9018'….}
How can I eliminate sublits or generate a new list without sublists, in which each element is unique.
To generate a new list you could iterate over the old one and throw out the elements you don't like.
Something like this
for i in rs_data:
if i in bad_values:
# do something
else:
# do something else
If you just want to eliminate duplicates it would be the best to use a set
Like this
mynewset = set(rs_data)
Is there any way of applying a function to every item in a set. For example, i want to make a every item in a set lowercase. If it was a list, i could do this as:
new_list = [item.lower() for item in old_list]
Obviously i could convert the set to a list, then do this, and then convert it back to a set again, but is there a more direct way?
You can simply use:
new_set = {set.lower() for item in old_set}
This is a set comprehension rather than a list comprehension.