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Why is it slower to iterate over a small string than a small list?
...unobvious, but is likely created from a greater number of checks on string indexing, with regards to the type and well-formedness. It is also quite likely thanks to the need to check what to return.
List indexing is remarkably fast.
>>> python3 -m timeit '[x for x in "abc"]'
1000000 l...
What does enumerate() mean?
...rt, it loops over the elements of an iterable (like a list), as well as an index number, combined in a tuple:
for item in enumerate(["a", "b", "c"]):
print item
prints
(0, "a")
(1, "b")
(2, "c")
It's helpful if you want to loop over a sequence (or other iterable thing), and also want to ha...
Remove duplicate rows in MySQL
...
A really easy way to do this is to add a UNIQUE index on the 3 columns. When you write the ALTER statement, include the IGNORE keyword. Like so:
ALTER IGNORE TABLE jobs
ADD UNIQUE INDEX idx_name (site_id, title, company);
This will drop all the duplicate rows. As an ...
How to raise a ValueError?
I have this code which finds the largest index of a specific character in a string, however I would like it to raise a ValueError when the specified character does not occur in a string.
...
How to fix HTTP 404 on Github Pages?
...Hub repository on the gh-pages branch.
Everything looks good, I have my index.html , my CSS, JS and pictures folders.
30...
How to get the current loop index when using Iterator?
...or to iterate through a collection
and I want to get the current element's index.
12 Answers
...
Handling click events on a drawable within an EditText
...presents the left drawable.
* */
public static final int DRAWABLE_INDEX_LEFT = 0;
/**
* This represents the top drawable.
* */
public static final int DRAWABLE_INDEX_TOP = 1;
/**
* This represents the right drawable.
* */
public static final int DRAWABLE_...
Asking the user for input until they give a valid response
...True:
try:
# Note: Python 2.x users should use raw_input, the equivalent of 3.x's input
age = int(input("Please enter your age: "))
except ValueError:
print("Sorry, I didn't understand that.")
#better try again... Return to the start of the loop
contin...
SQL SELECT speed int vs varchar
...at ints take up much less space than varchars.
This holds true both for unindexed and indexed access. The fastest way to go is an indexed int column.
As I see you've tagged the question postgreql, you might be interested in the space usage of different date types:
int fields occupy between 2 a...
How can I find the length of a number?
..."Starting weissteinLength length.");
let startTime = Date.now();
for (let index = 0; index < iterations; index++) {
weissteinLength(Math.random() * maxSize);
}
console.log("Ended weissteinLength length. Took : " + (Date.now() - startTime ) + "ms");
// ------- String length slowest.
conso...