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vagrant up failed, /dev/vboxnetctl: no such file or directory
Can be useful, I found this error. The common solution is reinstall virtualbox but there are a better way.
8 Answers
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How to convert string to boolean php
...ted by @lauthiamkok in the comments. I'm posting it here as an answer to call more attention to it.
Depending on your needs, you should consider using filter_var() with the FILTER_VALIDATE_BOOLEAN flag.
filter_var( true, FILTER_VALIDATE_BOOLEAN); // true
filter_var( 'true', FILTER_VALIDATE_...
Zip lists in Python
...x. list, string, tuple, dictionary)
Output (list)
1st tuple = (element_1 of numbers, element_1 of letters)
2nd tuple = (e_2 numbers, e_2 letters)
…
n-th tuple = (e_n numbers, e_n letters)
List of n tuples: n is the length of the shortest argument (input)
len(numbers) =...
Sending files using POST with HttpURLConnection
...one can provide me with a good example on how to send a bitmap "file" (actually an in-memory stream) via POST to an Apache HTTP server. I'm not interested in cookies or authentication or anything complicated, but I just want to have a reliable and logic implementation. All the examples that I've see...
Is it more efficient to copy a vector by reserving and copying, or by creating and swapping? [duplic
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@rlbond Accidentally downvoted the answer :(, Can you please edit the post, so that i can remove the downvote and give the upvote?
– Shubham Sharma
Jul 24 at 17:32
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MySQL Orderby a number, Nulls last
... tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://troels.arvin.dk/db/rdbms#select-order_by
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App Inventor 2 OCR文字识别教程 - 百度云与本地识别方案 · App Inventor 2 中文网
...费1000次
2. 获取Access Token
global 百度API_KEY = "your-api-key"
global 百度SECRET_KEY = "your-secret-key"
when Screen1.Initialize {
var Token_URL = "https://aip.baidubce.com/oauth/2.0/token?grant_type=client_credentials" +
"&client_id=" + 百度API_KEY +
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HashSet versus Dictionary w.r.t searching time to find if an item exists
...s for Dictionary is so fast that there is no benefit from using HashSet at all, in the OP's case.
– EtherDragon
Jul 27 '12 at 23:03
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Is there a 'box-shadow-color' property?
... That's a great use of variables! Let's hope that they'll be supported in all browsers within the next few years :/
– fregante
Aug 18 '15 at 0:10
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Trimming a huge (3.5 GB) csv file to read into R
... expert at this, but you might consider trying MapReduce, which would basically mean taking a "divide and conquer" approach. R has several options for this, including:
mapReduce (pure R)
RHIPE (which uses Hadoop); see example 6.2.2 in the documentation for an example of subsetting files
Alterna...