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Understanding the map function
...ld recommend using list comprehensions instead:
map(f, iterable)
is basically equivalent to:
[f(x) for x in iterable]
map on its own can't do a Cartesian product, because the length of its output list is always the same as its input list. You can trivially do a Cartesian product with a list co...
What is the difference between require() and library()?
...t; test <- library("abc")
Error in library("abc") : there is no package called 'abc'
> test
Error: object 'test' not found
> test <- require("abc")
Loading required package: abc
Warning message:
In library(package, lib.loc = lib.loc, character.only = TRUE, logical.return = TRUE, :
the...
Apache Commons equals/hashCode builder [closed]
...n allows for short-circuiting the evaluation if an earlier Object.equals() call returns false (to be fair: commons / lang has an ObjectUtils.equals(obj1, obj2) method with identical semantics which could be used instead of EqualsBuilder to allow short-circuiting as above).
So: yes, the commons lang...
Stop node.js program from command line
...an also kill it manually like this:
ps aux | grep node
Find the process ID (second from the left):
kill -9 PROCESS_ID
This may also work
killall node
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How to set default values in Rails?
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Try it. It'll work on new model objects called with the .new class method. That blog post's discussion about ActiveRecord directly calling .allocate was about model objects loaded with existing data from the database. (And it's a terrible idea for ActiveRecord to...
jQuery - Illegal invocation
...his helps me remember that it represents a jQuery object which helps avoid calling a method on something that's a string or trying to manipulate a string with .toString() or something when it's a jQuery object.
– timbrown
Apr 16 '13 at 15:13
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Most common way of writing a HTML table with vertical headers?
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First, your second option isn't quite valid HTML in the sense that all of the rows (TR) in a table should contain an equal number of columns (TD). Your header has 1 while the body has 3. You should use the colspan attribute to fix that.
Reference: "The THEAD, TFOOT...
What is a mixin, and why are they useful?
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@hillel good point, but keep in mind that Python will call superclasses' methods from left to right (when you need to override the constructor, for example).
– Eliseu Monar dos Santos
Jun 16 '15 at 8:23
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Random float number generation
...n will often not be sufficient if you need truly random numbers.
Before calling rand(), you must first "seed" the random number generator by calling srand(). This should be done once during your program's run -- not once every time you call rand(). This is often done like this:
srand (static_c...
JavaScript console.log causes error: “Synchronous XMLHttpRequest on the main thread is deprecated…”
...you return HTML content like that via xhr, you will cause jQuery to make a call to get that script. That call happens with an async flag false since it assumes you need the script to continue loading.
In situations like this one you'd be better served by looking into a binding framework of some ki...