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Converting between datetime, Timestamp and datetime64
...
I think this is the best answer I've ever seen. Coming from Excel, VBA, SAS, or SQL, Python seems weird because there's not just "one way" to work with dates/times. As with many things in Python or R, it seems one must choose a favourite method/...
Build a Basic Python Iterator
...2.x))
create a class that Python can iterate over on its own (defines __getitem__)
Examples:
# generator
def uc_gen(text):
for char in text.upper():
yield char
# generator expression
def uc_genexp(text):
return (char for char in text.upper())
# iterator protocol
class uc_iter():...
Check if option is selected with jQuery, if not select a default
... help some people I'm sure.
To check if a select element has any selected items:
if ($('#mySelect option:selected').length > 0) { alert('has a selected item'); }
or to check if a select has nothing selected:
if ($('#mySelect option:selected').length == 0) { alert('nothing selected'); }
or ...
“document.getElementByClass is not a function”
...bably meant document.getElementsByClassName() (and then grabbing the first item off the resulting node list):
var stopMusicExt = document.getElementsByClassName("stopButton")[0];
stopButton.onclick = function() {
var ta = document.getElementsByClassName("stopButton")[0];
document['player']...
Ruby capitalize every word first letter
...n the &:method syntax in map is a concise way to call a method on each item in the array. You can then call join to turn that array into a string. The * ' ' is an alternative way to call join. You can think of it as multiplying the items in the array together to create a string.
...
how to edit .csproj file
...st install this tool in visual studio
https://marketplace.visualstudio.com/items?itemName=EdMunoz.EditProj
and then right click edit you will have a new menu item Edit Project File :)
share
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imp...
How to find and return a duplicate value in array
...onclusion
Many of the answers are reasonable but using a Set is the clear best choice. It is fastest in the medium-hard cases, joint fastest in the hardest and only in computationally trivial cases - when your choice won't matter anyway - can it be beaten.
The one very special case in which you m...
How to format numbers as currency string?
...or)
/*
according to [https://stackoverflow.com/questions/411352/how-best-to-determine-if-an-argument-is-not-sent-to-the-javascript-function]
the fastest way to check for not defined parameter is to use typeof value === 'undefined'
rather than doing value === undefined.
*/
t = ...
What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
...tion of cause we need to use NOT operations and thats why they are exists. Best practise is it avoid them when we have any other alternative solutions.
– Lahiru Cooray
Jun 13 '16 at 3:47
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What is PECS (Producer Extends Consumer Super)?
...dr: "PECS" is from the collection's point of view. If you are only pulling items from a generic collection, it is a producer and you should use extends; if you are only stuffing items in, it is a consumer and you should use super. If you do both with the same collection, you shouldn't use either ext...