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Using Java 8's Optional with Stream::flatMap
...latMap(Optional::stream)
.findFirst();
Java 8
Yes, this was a small hole in the API, in that it's somewhat inconvenient to turn an Optional<T> into a zero-or-one length Stream<T>. You could do this:
Optional<Other> result =
things.stream()
.map(this::resolv...
Read an Excel file directly from a R script
...e gdata package works most of the time (although you need to have Perl installed on your system -- usually already true on MacOS and Linux, but takes an extra step on Windows, i.e. see http://strawberryperl.com/). There are various caveats, and alternatives, listed on the R wiki page.
The only reas...
Sort a Map by values
...
totally ripped this, but credited @CarterPage in the comments (it'll be in an open source project anyway). thanks so much.
– Nathan Beach
Sep 2 '15 at 3:07
...
How to refresh app upon shaking the device?
...trong "shake" when the application starts and "hits" the ground from free-fall. However, the code gets used to the gravitation due to the low-cut filter and would work also on other planets or in free space, once it is initialized.
(you never know how long your application will be in use...;-)
...
Is Ruby pass by reference or by value?
...en I perform a save on the @user object I lose the errors that were initially stored in the lang_errors variable.
13 An...
How to print out the contents of a vector?
...pes, if they are available and appropriate. std::vector has a member type called size_type for this job: it is the type returned by the size method.
// Path typedef'd to std::vector<char>
for( Path::size_type i=0; i<path.size(); ++i)
std::cout << path[i] << ' ';
Why not just ...
Selecting and manipulating CSS pseudo-elements such as ::before and ::after using jQuery
... using jQuery, for slightly shorter code.
Pros: any string can be dynamically inserted into the style
Cons: original styles aren't altered, just overridden; repeated (ab)use can make the DOM grow arbitrarily large
3) Alter a different DOM attribute
You can also to use attr() in your CSS to re...
How to solve error “Missing `secret_key_base` for 'production' environment” (Rails 4.1)
...and Enter for save and exit in vi.
But if you login as normal user, let's call it "example_user" for this gist, you will need to find one of these other files:
$ vi ~/.bash_profile
$ vi ~/.bash_login
$ vi ~/.profile
These files are in order of importance, which means that if you have the first fi...
Shortest distance between a point and a line segment
...ode, in C++. It presumes a class 2D-vector class vec2 {float x,y;}, essentially, with operators to add, subract, scale, etc, and a distance and dot product function (i.e. x1 x2 + y1 y2).
float minimum_distance(vec2 v, vec2 w, vec2 p) {
// Return minimum distance between line segment vw and point ...
What is the difference between i++ and ++i?
... Neither statement is correct. Consider your first statement. i++ actually means "save the value, increment it, store it in i, then tell me the original saved value". That is, the telling happens after the incrementing, not before as you have stated it. Consider the second statement. i++ actual...