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In Python, when to use a Dictionary, List or Set?
... and x not in l
l[i], l[i:j], l[i:j:k]
len(l), min(l), max(l)
l.count(x)
l.index(x[, i[, j]]) - index of the 1st occurrence of x in l (at or after i and before j indeces)
A list also implements all of the mutable sequence operations:
l[i] = x - item i of l is replaced by x
l[i:j] = t - slice of ...
Delete column from SQLite table
I have a problem: I need to delete a column from my SQLite database. I wrote this query
10 Answers
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How can I access and process nested objects, arrays or JSON?
...const value = arr[5]; // arr.5 would be a syntax error
// property name / index as variable
const x = 5;
const value = arr[x];
Wait... what about JSON?
JSON is a textual representation of data, just like XML, YAML, CSV, and others. To work with such data, it first has to be converted to JavaScri...
Heatmap in matplotlib with pcolor?
...pen("http://datasets.flowingdata.com/ppg2008.csv")
nba = pd.read_csv(page, index_col=0)
# Normalize data columns
nba_norm = (nba - nba.mean()) / (nba.max() - nba.min())
# Sort data according to Points, lowest to highest
# This was just a design choice made by Yau
# inplace=False (default) ->tha...
Can I see changes before I save my file in Vim?
...&& rm /tmp/tempFile
(Then open readonly and close vimdiff using :qall)
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Using varchar(MAX) vs TEXT on SQL Server
...regard to if you should use LIKE to search, or if you should use Full Text Indexing and CONTAINS. This question is the same regardless of VARCHAR(MAX) or TEXT.
If you are searching large amounts of text and performance is key then you should use a Full Text Index.
LIKE is simpler to implement and ...
What linux shell command returns a part of a string? [duplicate]
...{parameter##remove_matching_prefix}
${parameter%%remove_matching_suffix}
Indexed substring expansion (special behaviours with negative offsets, and, in newer Bashes, negative lengths):
${parameter:offset}
${parameter:offset:length}
${parameter:offset:length}
And of course, the much useful expan...
Encoding URL query parameters in Java
How does one encode query parameters to go on a url in Java? I know, this seems like an obvious and already asked question.
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How to revert uncommitted changes including files and folders?
...here a git command to revert all uncommitted changes in a working tree and index and to also remove newly created files and folders?
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Asynchronous Process inside a javascript for loop [duplicate]
...e some time in the future and call their callbacks, the value of your loop index variable i will be at its last value for all the callbacks.
This is because the for loop does not wait for an asynchronous operation to complete before continuing on to the next iteration of the loop and because the ...