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In-place type conversion of a NumPy array
...Py array of int32 , how do I convert it to float32 in place ? So basically, I would like to do
6 Answers
...
Calculate distance between 2 GPS coordinates
...y solution:
#include <math.h>
#include "haversine.h"
#define d2r (M_PI / 180.0)
//calculate haversine distance for linear distance
double haversine_km(double lat1, double long1, double lat2, double long2)
{
double dlong = (long2 - long1) * d2r;
double dlat = (lat2 - lat1) * d2r;
...
Looping through a hash, or using an array in PowerShell
... how:
$hash = @{
a = 1
b = 2
c = 3
}
$hash.Keys | % { "key = $_ , value = " + $hash.Item($_) }
Output:
key = c , value = 3
key = a , value = 1
key = b , value = 2
share
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improve th...
When is std::weak_ptr useful?
...want to keep them in memory, so you hold a strong pointer to them. Periodically, you scan the cache and decide which objects have not been accessed recently. You don't need to keep those in memory, so you get rid of the strong pointer.
But what if that object is in use and some other code holds a s...
Why Choose Struct Over Class?
...es in many circumstances.
Structs are preferable if they are relatively small and copiable because copying is way safer than having multiple references to the same instance as happens with classes. This is especially important when passing around a variable to many classes and/or in a multithreaded...
How to install packages using pip according to the requirements.txt file from a local directory?
...
This works for me:
$ pip install -r requirements.txt --no-index --find-links file:///tmp/packages
--no-index - Ignore package index (only looking at --find-links URLs instead).
-f, --find-links <URL> - If a URL or path to an html file, then par...
Nested defaultdict of defaultdict
...
For an arbitrary number of levels:
def rec_dd():
return defaultdict(rec_dd)
>>> x = rec_dd()
>>> x['a']['b']['c']['d']
defaultdict(<function rec_dd at 0x7f0dcef81500>, {})
>>> print json.dumps(x)
{"a": {"b": {"c": {"d": {}}}}}
...
getting exception “IllegalStateException: Can not perform this action after onSaveInstanceState”
... working perfectly for API < 11, and Force Closing on API > 11.
I really couldn't figure out what they changed inside the Activity lifecycle in the call to saveInstance, but I here is how I solved this :
@Override
protected void onSaveInstanceState(Bundle outState) {
//No call for super(...
Display block without 100% width
... gets positioned before the last span. Guess one solution would be to make all child elements in the li float.
– Staffan Estberg
Oct 3 '12 at 17:01
...
CALayers didn't get resized on its UIView's bounds change. Why?
...you sure? it sounds like you are describing frame. bounds should, theoretically, always have 0,0 as its origin.
– griotspeak
Feb 11 '12 at 2:32
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