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Pandas aggregate count distinct
Let's say I have a log of user activity and I want to generate a report of total duration and the number of unique users per day.
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Delete a key from a MongoDB document using Mongoose
... can do:
User.update({_id: user._id}, {$unset: {field: 1 }}, callback);
And since version 2.4, if you have an instance of a model already you can do:
doc.field = undefined;
doc.save(callback);
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How to add leading zeros?
...s of 10 width 8 too.
anim <- 25499:25504
x <- 10 ^ (0:5)
paste (and it's variant paste0) are often the first string manipulation functions that you come across. They aren't really designed for manipulating numbers, but they can be used for that. In the simple case where we always have t...
Has Facebook sharer.php changed to no longer accept detailed parameters?
...eters in sharer.php
The sharer will no longer accept custom parameters and facebook will
pull the information that is being displayed in the preview the same
way that it would appear on facebook as a post from the url OG meta
tags.
Use dialog/feeds instead of sharer.php
https://www.face...
Correct way of using JQuery-Mobile/Phonegap together?
What is the correct way (to this date) to use JQuery Mobile and Phonegap together?
9 Answers
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Why does `a == b or c or d` always evaluate to True?
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In many cases, Python looks and behaves like natural English, but this is one case where that abstraction fails. People can use context clues to determine that "Jon" and "Inbar" are objects joined to the verb "equals", but the Python interpreter is more...
How do you make a LinearLayout scrollable?
I have lot of items on the screen and I need to use the scrollbar so the user can scroll down. However, the scroll is either not visible or it's not working. How is it possible to add a scrollbar to a LinearLayout ?
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CSS two divs next to each other
... <div> s next to each other. The right <div> is about 200px; and the left <div> must fill up the rest of the screen width? How can I do this?
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How to determine if Javascript array contains an object with an attribute that equals a given value?
...is from 2011, before browsers had widely supported array filtering methods and arrow functions. Have a look at CAFxX's answer.
There is no "magic" way to check for something in an array without a loop. Even if you use some function, the function itself will use a loop. What you can do is break out ...
Solving “The ObjectContext instance has been disposed and can no longer be used for operations that
...rties should be marked as virtual - EF creates proxy class for your entity and overrides navigation properties to allow lazy-loading. E.g. if you have this entity:
public class MemberLoan
{
public string LoandProviderCode { get; set; }
public virtual Membership Membership { get; set; }
}
En...