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What does the “Just” syntax mean in Haskell?
...r integer functions that are meant to return Natural numbers (for example, String.indexOf - when a substring is not found, the returned index is commonly designed to be negative)
return a special value (pointer): NULL or some such
silently return without doing anything: for example, lend could be wr...
Convert pandas timezone-aware DateTimeIndex to naive timestamp, but in certain timezone
..., the data is offset appropriately and +01:00 (or similar) is added to the string. Stripping off the tz_info value (using tz_convert(tz=None)) doesn't doesn't actually change the data that represents the naive part of the timestamp.
So, the only way to do what you want is to modify the underlyin...
Append text to input field
...are two options. Ayman's approach is the most simple, but I would add one extra note to it. You should really cache jQuery selections, there is no reason to call $("#input-field-id") twice:
var input = $( "#input-field-id" );
input.val( input.val() + "more text" );
The other option, .val() can ...
case-insensitive list sorting, without lowercasing the result?
I have a list of strings like this:
8 Answers
8
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What is the fastest way to compute sin and cos together?
...os instruction delivers somewhat more accuracy (double extended), but that extra accuracy gets thrown away in most programs that call the sin function, as its result is usually rounded to double precision by later arithmetic operations or a store to memory. In most situations, they deliver the same...
Separation of business logic and data access in django
... standard method in the forms API; it is intended to replace the
'extract-data-from-form-in-view-and-do-stuff' pattern by a more testable pattern.
"""
user_id = self.cleaned_data['user_id']
user = User.objects.get(pk=user_id)
# set active flag
user...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...rated threadsafe -- but this is much faster than the atomic property since extra checks are eliminated.
strong is used with ARC and it basically helps you , by not having to worry about the retain count of an object. ARC automatically releases it for you when you are done with it.Using the keyword s...
How to append rows to an R data frame
...<- function(n){
df <- data.frame(x = numeric(n), y = character(n), stringsAsFactors = FALSE)
for(i in 1:n){
df$x[i] <- i
df$y[i] <- toString(i)
}
df
}
Here's a similar approach, but one where the data.frame is created as the last step.
# Use preallocated vectors
f4 <...
What is context in _.each(list, iterator, [context])?
...pluck, 2);
Even from the limited examples, you can see how powerful an "extra argument" can be for creating re-usable code. Instead of making a different callback function for each situation, you can usually adapt a low-level helper. The goal is to have your custom logic bundling a verb and two n...
Cooler ASCII Spinners? [closed]
...
you get extra points if you can make a popping sound with they system speaker!
– RCIX
Apr 22 '10 at 1:51
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