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Replace specific characters within strings
... fixed=TRUE prevents R from using regular expressions, which allow more flexible pattern matching but take time to compute. If all that's needed is removing a single constant string "e", they aren't necessary.
– mm689
Oct 31 '16 at 19:16
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What is the point of Lookup?
... via that key in an efficient manner (rather than just iterating over them all, which is what GroupBy lets you do).
For example, you could take a load of .NET types and build a lookup by namespace... then get to all the types in a particular namespace very easily:
using System;
using System.Collec...
How to modify a text file?
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This is an operating system thing, not a Python thing. It is the same in all languages.
What I usually do is read from the file, make the modifications and write it out to a new file called myfile.txt.tmp or something like that. This is better than reading the whole file into memory because the f...
How to remove “Server name” items from history of SQL Server Management Studio
When trying to connect to a server in Management Studio (specifically 2008), there is a field where you enter the Server name. That field also has a drop-down list where it shows a history of servers that you have attempted to connect to.
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Is there a way of setting culture for a whole application? All current threads and new threads?
Is there a way of setting culture for a whole application? All current threads and new threads?
10 Answers
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Can I make a function available in every controller in angular?
If I have a utility function foo that I want to be able to call from anywhere inside of my ng-app declaration. Is there someway I can make it globally accessible in my module setup or do I need to add it to the scope in every controller?
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If list index exists, do X
... that relative index from the end of the list...
However, by definition, all items in a Python list between 0 and len(the_list)-1 exist (i.e., there is no need for a try, except if you know 0 <= index < len(the_list)).
You can use enumerate if you want the indexes between 0 and the last el...
Copy array items into another array
...y . Except I don't want newArray[0] to be dataArray . I want to push in all the items into the new array:
16 Answers
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Extract a regular expression match
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Use the new stringr package which wraps all the existing regular expression operates in a consistent syntax and adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1]...
What's the difference between a single precision and double precision floating point operation?
...as the greater data precision available with 64-bit data types is not typically required by 3D games, as well as the fact that processing 64-bit data uses twice as much RAM, cache, and bandwidth, thereby reducing the overall system performance.
From Webopedia:
The term double precision is some...