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Check if application is on its first run [duplicate]
I am new to android development and and I want to setup some of application's attributes based on Application first run after installation. Is there any way to find that the application is running for the first time and then to setup its first run attributes?
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Python argparse command line flags without arguments
... after -w on the command line. If you are just looking to flip a switch by setting a variable True or False, have a look at http://docs.python.org/dev/library/argparse.html#action (specifically store_true and store_false)
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('-w',...
How to center a subview of UIView
...y have your subview centered regardless of what your parent view center is set to.
– Old Name
Jul 23 '14 at 23:28
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What does “O(1) access time” mean?
... like 14 nanoseconds, or three minutes no matter the amount of data in the set.
O(n) means it takes an amount of time linear with the size of the set, so a set twice the size will take twice the time. You probably don't want to put a million objects into one of these.
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Non-type template parameters
... editor after snippets, if snippets enabled
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What is the fastest or most elegant way to compute a set difference using Javascript arrays?
Let A and B be two sets. I'm looking for really fast or elegant ways to compute the set difference ( A - B or A \B , depending on your preference) between them. The two sets are stored and manipulated as Javascript arrays, as the title says.
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find -exec a shell function in Linux?
Is there a way to get find to execute a function I define in the shell? For example:
14 Answers
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Histogram using gnuplot?
...ooth freq to see why the above makes a histogram
to deal with ranges just set the xrange variable.
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How to create fixed space and flexible space bar button items programmatically?
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Note that to set the width of a Fixed Space UIBarButtonItem, you need to set the .width property.
– Nick Forge
May 31 '11 at 8:18
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What's the fastest way to merge/join data.frames in R?
...eSQL databases as well.
library(plyr)
library(data.table)
library(sqldf)
set.seed(123)
N <- 1e5
d1 <- data.frame(x=sample(N,N), y1=rnorm(N))
d2 <- data.frame(x=sample(N,N), y2=rnorm(N))
g1 <- sample(1:1000, N, replace = TRUE)
g2<- sample(1:1000, N, replace = TRUE)
d <- data.fram...