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How to Correctly Use Lists in R?
...st?) contemporary programming languages in widespread use have at least a handful of ADTs [abstract data types] in common, in particular,
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What are the differences between local branch, local tracking branch, remote branch and remote track
I just started using Git and I got really confused between different branches. Can anyone help me to figure out what the following branch types are?
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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)...
Fast check for NaN in NumPy
... to get slower as NaNs get closer to the start of the array. On the other hand, sum's throughput seems constant regardless of whether there are NaNs and where they're located:
In [40]: x = np.random.rand(100000)
In [41]: %timeit np.isnan(np.min(x))
10000 loops, best of 3: 153 us per loop
In [42]:...
Rotating and spacing axis labels in ggplot2
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In the newest version of ggplot2 the command would be: q + theme(axis.text.x=element_text(angle = -90, hjust = 0))
– rnorberg
Sep 28 '12 at 13:18
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CORS Access-Control-Allow-Headers wildcard being ignored?
...cards in the Access-Control-Allow-Headers header was added to the living standard only in May 2016, so it may not be supported by all browsers. On browser which don't implement this yet, it must be an exact match: https://www.w3.org/TR/2014/REC-cors-20140116/#access-control-allow-headers-response-he...
best practice to generate random token for forgot password
...ier for forgot password . I read i can do it by using timestamp with mt_rand(), but some people are saying that time stamp might not be unique every time. So i am bit of confused here. Can i do it with using time stamp with this ?
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Explanation of strong and weak storage in iOS5
I am new to iOS5 development and using objective-c. I have trouble understanding the difference between strong and weak storage. I have read the documentation and other SO questions, but they all sound identical to me with no further insight.
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How to count the number of set bits in a 32-bit integer?
...ays addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's popcnt, on CPUs where it's supported)...
Why does @foo.setter in Python not work for me?
So, I'm playing with decorators in Python 2.6, and I'm having some trouble getting them to work. Here is my class file:
4 A...