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Android accelerometer accuracy (Inertial navigation)
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I realise this is a long time ago, but I've got a follow-up question. The camera in Android JB has a 'panorama' feature, which lets you take a panoramic picture by moving the phone, either rotating it or moving it linearly along one axis. To do thi...
How to automatically install Emacs packages by specifying a list of package names?
...ts)) from the accepted answer. The package refresh here increases startup time on systems that already have the packages installed. The rest of this answer is perfect, though.
– rfinz
Feb 26 '14 at 21:47
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How to access the ith column of a NumPy multidimensional array?
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And if you want to access more than one column at a time you could do:
>>> test = np.arange(9).reshape((3,3))
>>> test
array([[0, 1, 2],
[3, 4, 5],
[6, 7, 8]])
>>> test[:,[0,2]]
array([[0, 2],
[3, 5],
[6, 8]])
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How to detect internet speed in JavaScript?
...oad image with a known file size then in its onload event measure how much time passed until that event was triggered, and divide this time in the image file size.
Example can be found here: Calculate speed using javascript
Test case applying the fix suggested there:
//JUST AN EXAMPLE, PLEASE...
What is token-based authentication?
...can offer the token - which
offers access to a specific resource
for a time period - to the remote
site.
In other words: add one level of indirection for authentication -- instead of having to authenticate with username and password for each protected resource, the user authenticates that wa...
What is the difference between printf() and puts() in C?
...nt of printf:
char * myMessage;
// ... myMessage gets assigned at runtime, unpredictable content
printf(myMessage); // <--- WRONG! (what if myMessage contains a '%' char?)
puts(myMessage); // ok
printf("%s\n",myMessage); // ok, equivalent to the previous, perhaps less efficient
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What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
... and assign the result... which in the majority case is going to be a a runtime array. You can avoid the overhead of looking for the global constructor by just using []. It may seem small, but when you're shooting for near real-time performance in your app, it can make a difference.
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C char array initialization
...illegal for this reason.
To initialize an array, you have to do it at the time of definition:
char buf [10] = ' ';
will give you a 10-character array with the first char being the space '\040' and the rest being NUL, i.e., '\0'. When an array is declared and defined with an initializer, the arra...
How do I put an already-running process under nohup?
I have a process that is already running for a long time and don't want to end it.
11 Answers
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How long do browsers cache HTTP 301s?
... find edge cases where it makes sense for a "permanent" redirect to have a time limit. Note that 302 and 307 redirects aren't cached by default by browsers.
If you previously issued a 301 redirect but want to un-do that
If people still have the cached 301 redirect in their browser they will continu...