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Extract a dplyr tbl column as a vector
...on to make pulling out a column a bit nicer (easier to type, and easier to read):
pull <- function(x,y) {x[,if(is.name(substitute(y))) deparse(substitute(y)) else y, drop = FALSE][[1]]}
This lets you do either of these:
iris2 %>% pull('Species')
iris2 %>% pull(Species)
iris2 %>% pull...
machine learning libraries in C# [closed]
...a choice. They don't use partial classes for their forms (makes it hard to read the code behind their samples), and i can't find decent documentation for it.
– RCIX
Oct 26 '09 at 10:58
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What is the bower (and npm) version syntax?
...won't try to detail it all here. Check it out on the node semver package's readme. And be sure to use the semantic versioning calculator while you're practicing and trying to get your head around how SemVer works.
RE: Non-Consecutive Version Numbers: OP's final question seems to be about specify...
Cleaning up sinon stubs easily
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If you are using sinon >5.0 read below. There's now a much easier method: stackoverflow.com/a/55251560/4464702
– RAnders00
Jul 5 '19 at 22:42
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When does invoking a member function on a null instance result in undefined behavior?
...tanding, if p were a hardware address which would trigger some action when read, but were not declared volatile, the statement *p; would not be required, but would be allowed, to actually read that address; the statement &(*p);, however, would be forbidden from doing so. If *p were volatile, th...
Parsing HTML using Python
...ontainer'}).text)
You don't need performance descriptions I guess - just read how BeautifulSoup works. Look at its official documentation.
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What are the pros and cons of performing calculations in sql vs. in your application
...; the server could be streaming rows which you consume as they arrive - a "reader" metaphor is not uncommon.
– Marc Gravell♦
Sep 22 '11 at 23:03
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Meaning of acronym SSO in the context of std::string
... a more realistic implementation, with the caveat that I've never actually read any implementation of SSO "in the wild".
Implementation details
At the minimum, a std::string needs to store the following information:
The size
The capacity
The location of the data
The size could be stored as a s...
Add disabled attribute to input element using Javascript
... this is the best answer: "you can use both... but it depends."
You should read this answer instead: https://stackoverflow.com/a/5876747/257493
And their release notes for that change are included here:
Neither .attr() nor .prop() should be used for getting/setting value. Use the .val() method inst...
configure: error: C compiler cannot create executables
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If you are reading this answer, this is definitely something you should do, but be aware that it will not solve your problem with other packages you are trying to build. So first install the command line tools then see the answer below ...