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How do I find all files containing specific text on Linux?
I'm trying to find a way to scan my entire Linux system for all files containing a specific string of text. Just to clarify, I'm looking for text within the file, not in the file name.
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Why aren't superclass __init__ methods automatically invoked?
...l distinction between Python's __init__ and those other languages constructors is that __init__ is not a constructor: it's an initializer (the actual constructor (if any, but, see later;-) is __new__ and works completely differently again). While constructing all superclasses (and, no doubt, doing ...
Java 8 Iterable.forEach() vs foreach loop
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The better practice is to use for-each. Besides violating the Keep It Simple, Stupid principle, the new-fangled forEach() has at least the following deficiencies:
Can't use non-final variables. So, code like the following can't be turned into a forEach la...
Conversion from Long to Double in Java
Is there any way to convert a Long data type to Double or double ?
8 Answers
8
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Get a UTC timestamp [duplicate]
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new Date().getTime();
For more information, see @James McMahon's answer.
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Drop data frame columns by name
...5,10),
a=11:20
)
drops <- c("x","z")
DF[ , !(names(DF) %in% drops)]
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT :
For those still not acquainted with the drop argument of the indexing function, if you want to ke...
Python None comparison: should I use “is” or ==?
My editor warns me when I compare my_var == None , but no warning when I use my_var is None .
3 Answers
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【转】用App Inventor 2实现电子围栏功能 - App应用开发 - 清泛IT社区，为创新赋能！
...相对复杂的部分，因此独立一章详细说明。
App Inventor自带地图组件，可以方便的实现电子围栏（地理围栏，Geofence）功能。
实现电子围栏需要的组件实现电子围栏需要用到地图Map容器，需要用到的组件有Map，类似画面，...
How to prevent favicon.ico requests?
I don't have a favicon.ico, but my browser always makes a request for it.
11 Answers
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What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
...g'.
I'd expect them to be translated into something reasonably efficient for your current platform, whether it be one of those fancy bit-twiddling algorithms, or a single instruction.
A useful trick if your input can be zero is __builtin_clz(x | 1): unconditionally setting the low bit without mo...