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cartesian product in pandas
...n unused column name, then add dummy columns with that name, merge, and finally drop the column on the result? Creating, as opposed to reading, data with pandas is just a pain
– Bananach
Oct 10 '19 at 7:31
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How to use php serialize() and unserialize()
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echo json_encode($array); How exactly you pass it depends on the circumstances. Don't get too hung up on that.
– deceze♦
Dec 27 '11 at 7:57
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Creating anonymous objects in php
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This is interesting but it doesn't really address the question, as the OP was asking about a convenient way to initialise an object with various members without creating a class. I am not sure whether anonymous classes in php can be used to do that, and if it ca...
How to programmatically set style attribute in a view
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Generally you can't change styles programmatically; you can set the look of a screen, or part of a layout, or individual button in your XML layout using themes or styles. Themes can, however, be applied programmatically.
There i...
How to find gaps in sequential numbering in mysql?
...rks on table of any size (not just on 100 rows):
SELECT (t1.id + 1) as gap_starts_at,
(SELECT MIN(t3.id) -1 FROM arrc_vouchers t3 WHERE t3.id > t1.id) as gap_ends_at
FROM arrc_vouchers t1
WHERE NOT EXISTS (SELECT t2.id FROM arrc_vouchers t2 WHERE t2.id = t1.id + 1)
HAVING gap_ends_at IS ...
Can I use a min-height for table, tr or td?
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It isn't nice at all!
– Ahmad
Aug 9 at 10:16
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How do I set a ViewModel on a window in XAML using DataContext property?
The question pretty much says it all.
5 Answers
5
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Default value in Doctrine
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I use both this and the accepted answer to cover all bases. Also just a note that you can also do: options={"default": 0} Be careful to use " and not ', as it causes errors in my version of doctrine.
– Scott Flack
Jun 17 '14 at 7:37
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Asynchronous Process inside a javascript for loop [duplicate]
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The for loop runs immediately to completion while all your asynchronous operations are started. When they complete 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 t...
How to get all properties values of a JavaScript Object (without knowing the keys)?
... for you:
for (var key in obj) {
if (Object.prototype.hasOwnProperty.call(obj, key)) {
var val = obj[key];
// use val
}
}
The nested if makes sure that you don't enumerate over properties in the prototype chain of the object (which is the behaviour you almost certainly wan...