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Matplotlib scatterplot; colour as a function of a third variable
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There's no need to manually set the colors. Instead, specify a grayscale colormap...
import numpy as np
import matplotlib.pyplot as plt
# Generate data...
x = np.random.random(10)
y = np.random.random(10)
# Plot...
plt.scatter(x, y, c=y, s=500)
plt.gray()
plt.show()
Or, if ...
When should we call System.exit in Java
In Java, What is the difference with or without System.exit(0) in following code?
10 Answers
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Find all records which have a count of an association greater than zero
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Well that is Rails for you. If you can provide an sql answer (and explain why this isn't efficient), that may be a lot more helpful.
– jvnill
May 7 '19 at 23:17
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In ASP.NET, when should I use Session.Clear() rather than Session.Abandon()?
...ntent) from the Object. The session with the same key is still alive.
So, if you use Session.Abandon(), you lose that specific session and the user will get a new session key. You could use it for example when the user logs out.
Use Session.Clear(), if you want that the user remaining in the same ...
Is there an equivalent to e.PageX position for 'touchstart' event as there is for click event?
...start', function(e) {
var xPos = e.originalEvent.touches[0].pageX;
});
If you want other fingers, you can find them in other indices of the touches list.
UPDATE FOR NEWER JQUERY:
$(document).on('touchstart', '#box', function(e) {
var xPos = e.originalEvent.touches[0].pageX;
});
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How can I define a composite primary key in SQL?
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Just for clarification: a table can have at most one primary key. A primary key consists of one or more columns (from that table). If a primary key consists of two or more columns it is called a composite primary key. It is defined as fol...
list_display - boolean icons for methods
When defining the list_display array for a ModelAdmin class, if a BooleanField or NullBooleanField is given the UI will use nice looking icons instead of True/False text in the column. If a method that returns a boolean is given, however, it simply prints out True/False.
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Automatically deleting related rows in Laravel (Eloquent ORM)
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This doesn't cascade it further though. For example if Photos has tags and you do the same in Photos model (i.e. on deleting method: $photo->tags()->delete();) it never gets trigger. But if I make it a for loop and do something like for($user->photos as $photo) { $pho...
Assertion failure in dequeueReusableCellWithIdentifier:forIndexPath:
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You're using the dequeueReusableCellWithIdentifier:forIndexPath: method. The documentation for that method says this:
Important: You must register a class or nib file using the registerNib:forCellReuseIdentifier: or registerClass:forCellReuseIdentifier: method befo...
SELECT * FROM X WHERE id IN (…) with Dapper ORM
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Marko, that IS important. And, if you are doing it that way, you might consider finding another way of querying your data, such as doing a join or an anti-join rather than passing a list of ids. The IN clause is not the most highly performing query and ca...