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Flatten an irregular list of lists
...
Using generator functions can make your example a little easier to read and probably boost the performance.
Python 2
def flatten(l):
for el in l:
if isinstance(el, collections.Iterable) and not isinstance(el, basestring):
for sub in flatten(el):
yield sub...
Should an Enum start with a 0 or a 1?
...ag enum values of zero unless the value represents "all flags are cleared" and is named appropriately, as prescribed by the next guideline.
✔️ DO name the zero value of flag enums None. For a flag enum, the value must always mean "all flags are cleared."
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How to append rows to an R data frame
...rs of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n)...
How can I measure the speed of code written in PHP? [closed]
... two solutions :
The quite "naïve" one is using microtime(true) tobefore and after a portion of code, to get how much time has passed during its execution ; other answers said that and gave examples already, so I won"t say much more.
This is a nice solution if you want to benchmark a couple of in...
Understanding Fragment's setRetainInstance(boolean)
...you leave the Activity by pressing the back button (thus, calling finish() and effectively destroying the Activity), all of the Activitys attached Fragments will also be destroyed.
Why doesn't it work with fragments on the back stack?
There are probably multiple reasons why it's not supported,...
Best practice to mark deprecated code in Ruby?
...a method as deprecated, so the people using it can easily check their code and catch up. In Java you set @Deprecated and everybody knows what this means.
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How do I Sort a Multidimensional Array in PHP [duplicate]
...a loaded into a multidimensional array. In this way each "row" is a record and each "column" contains the same type of data. I am using the function below to load my CSV file.
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jQuery get textarea text
Recently I have started playing with jQuery, and have been following a couple of tutorials. Now I feel slightly competent with using it (it's pretty easy), and I thought it would be cool if I were able to make a 'console' on my webpage (as in, you press the ` key like you do in FPS games, etc.), a...
How do I include a file over 2 directories back?
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@Brian Well, that’s nonsense, you’re comparing apples and oranges. You’re right that a define would be used here but (1) that wasn’t even remotely the question here. And (2) you’d still use a relative path in your define, Unless you actually hard-code the whole absolute se...
SQLiteDatabase.query method
...By using the Where/Bind -Args version you get automatically escaped values and you don't have to worry if input-data contains '.
Unsafe: String whereClause = "column1='" + value + "'";
Safe: String whereClause = "column1=?";
because if value contains a ' your statement either breaks and you get ex...