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What are the options for storing hierarchical data in a relational database? [closed]
...in this thread suggested. Use an Adjacency List to maintain the hierarchy and use Nested Sets to query the hierarchy.
The problem up until now has been that the coversion method from an Adjacecy List to Nested Sets has been frightfully slow because most people use the extreme RBAR method known as ...
For loop for HTMLCollection elements
...x. So, to get the value from the pseudo-array, you'd have to do list[key] and to get the id, you'd do list[key].id. But, you should not be doing this with for/in in the first place.
Summary (added in Dec 2018)
Do not ever use for/in to iterate a nodeList or an HTMLCollection. The reasons to avo...
How do I give text or an image a transparent background using CSS?
...r: rgba(255, 0, 0, 0.5);
Here's an article from css3.info, Opacity, RGBA and compromise (2007-06-03).
<p style="background-color: rgba(255, 0, 0, 0.5);">
<span>Hello, World!</span>
</p>
...
What's the concept of and differences between Framebuffer and Renderbuffer in OpenGL?
I'm confused about concept of Framebuffer and Renderbuffer. I know that they're required to render, but I want to understand them before use.
...
bash/fish command to print absolute path to a file
Question: is there a simple sh/bash/zsh/fish/... command to print the absolute path of whichever file I feed it?
20 Answers...
What are all the user accounts for IIS/ASP.NET and how do they differ?
...with ASP.NET 4.0 installed there is a whole slew of related user accounts, and I can't understand which one is which, how to they differ, and which one is REALLY the one that my app runs under. Here's a list:
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How to parse JSON in Java
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I agree with @StaxMan. I just tried org.json and it's horribly cumbersome. It really doesn't play with with standard Java Collection types, for example.
– Ken Williams
Nov 12 '14 at 16:55
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How to pretty-print a numpy.array without scientific notation and with given precision?
...printoptions to set the precision of the output:
import numpy as np
x=np.random.random(10)
print(x)
# [ 0.07837821 0.48002108 0.41274116 0.82993414 0.77610352 0.1023732
# 0.51303098 0.4617183 0.33487207 0.71162095]
np.set_printoptions(precision=3)
print(x)
# [ 0.078 0.48 0.413 0.83 ...
Is it better to call ToList() or ToArray() in LINQ queries?
...lare it. This is usually because I need to iterate over it multiple times and it is expensive to compute. For example:
16...
Speed up the loop operation in R
... over a data.frame object. It simply adds a new column to a data.frame and accumulates something. (simple operation). The data.frame has roughly 850K rows. My PC is still working (about 10h now) and I have no idea about the runtime.
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