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Replace all 0 values to NA
... has a 0 value which should be considered as null in statistical analysis. What is the fastest way to replace all the 0 value to NULL in R?
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What is the use of “assert” in Python?
...nswer get so many up votes, actually others answers also. the question is "What is the use of “assert” in Python? ", so it is asking: when to use, or more exactly: what is the usage scenario of assert, but after reading all answers, i totally got nothing i want!
– lnshi
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What is the direction of stack growth in most modern systems?
....org/wiki/Calling_convention
See also
Why does the stack grow downward?
What are the advantages to having the stack grow downward?
Why do stacks typically grow downwards?
Does stack grow upward or downward?
share
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How do I resolve “HTTP Error 500.19 - Internal Server Error” on IIS7.0 [closed]
What causes this error, how can I fix it?
31 Answers
31
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How do I convert from int to String?
... smell as it suggests the author doesn't know about the two methods above (what else might they not know?).
Java has special support for the + operator when used with strings (see the documentation) which translates the code you posted into:
StringBuilder sb = new StringBuilder();
sb.append("");
s...
What is the purpose of setting a key in data.table?
...hich require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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What's the “average” requests per second for a production web application?
I have no frame of reference in terms of what's considered "fast"; I'd always wondered this but have never found a straight answer...
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How can I pair socks from a pile efficiently?
...(A 3D cuboid would also work, but that is not very practical.)
Update:
What about parallelism? Can multiple humans match the socks faster?
The simplest parallelization strategy is to have multiple workers take from the input basket and put the socks onto the piles. This only scales up so much ...
Software Design vs. Software Architecture [closed]
...stem is its 'skeleton'. It's the highest level of abstraction of a system. What kind of data storage is present, how do modules interact with each other, what recovery systems are in place. Just like design patterns, there are architectural patterns: MVC, 3-tier layered design, etc.
Software desig...
What is array to pointer decay?
What is array to pointer decay? Is there any relation to array pointers?
9 Answers
9
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