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Reading binary file and looping over each byte
...hile byte != "":
# Do stuff with byte.
byte = f.read(1)
finally:
f.close()
Python 2.5-2.7
with open("myfile", "rb") as f:
byte = f.read(1)
while byte != "":
# Do stuff with byte.
byte = f.read(1)
Note that the with statement is not available in versio...
Automatic Retina images for web sites
...
There is a new attribute for the img tag that allows you to add a retina src attribute, namely srcset. No javascript or CSS needed, no double loading of images.
<img src="low-res.jpg" srcset="high-res.jpg 2x">
Browser Support: http://caniuse.com/#search=srcset
O...
Exit codes in Python
...
What you're looking for in the script is calls to sys.exit(). The argument to that method is returned to the environment as the exit code.
It's fairly likely that the script is never calling the exit method, and that 0 is the default exit code.
...
Set a default parameter value for a JavaScript function
...S2015, default parameters are in the language specification.
function read_file(file, delete_after = false) {
// Code
}
just works.
Reference: Default Parameters - MDN
Default function parameters allow formal parameters to be initialized with default values if no value or undefined is pass...
How to emulate C array initialization “int arr[] = { e1, e2, e3, … }” behaviour with std::array?
...s question is about not having to specify the number of elements and still allow nested types to be directly initialized.)
This question discusses the uses left for a C array like int arr[20]; . On his answer , @James Kanze shows one of the last strongholds of C arrays, it's unique initializat...
Vertically align text next to an image?
...
Actually, in this case it's quite simple: apply the vertical align to the image. Since it's all in one line, it's really the image you want aligned, not the text.
<!-- moved "vertical-align:middle" style from span to img ...
IOS: verify if a point is inside a rect
...edited Oct 11 '19 at 11:30
denis_lor
5,10144 gold badges1717 silver badges4141 bronze badges
answered Nov 7 '11 at 14:23
...
Join strings with a delimiter only if strings are not null or empty
...
.filter(Boolean) (which is the same as .filter(x => x)) removes all "falsy" values (nulls, undefineds, empty strings etc). If your definition of "empty" is different, then you'll have to provide it, for example:
[...].filter(x => typeof x === 'string' && x.length > 0)
wi...
Extract a substring according to a pattern
... sub to replace it with a colon first. For example, if the separator were _ then string <- sub("_", ":", string)
c(read.dcf(textConnection(string)))
## [1] "E001" "E002" "E003"
7) separate
7a) Using tidyr::separate we create a data frame with two columns, one for the part before the colon and o...
Is it possible to print a variable's type in standard C++?
...at I'm recommending below is:
template <typename T> std::string type_name();
which would be used like this:
const int ci = 0;
std::cout << type_name<decltype(ci)>() << '\n';
and for me outputs:
int const
<disclaimer> I have not tested this on MSVC. </disclai...