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Why is it slower to iterate over a small string than a small list?
...ter strings are cached.
The difference is unobvious, but is likely created from a greater number of checks on string indexing, with regards to the type and well-formedness. It is also quite likely thanks to the need to check what to return.
List indexing is remarkably fast.
>>> python...
Append a dictionary to a dictionary [duplicate]
...hat if extra and orig have overlapping keys, the final value will be taken from extra. For example,
>>> d1 = {1: 1, 2: 2}
>>> d2 = {2: 'ha!', 3: 3}
>>> d1.update(d2)
>>> d1
{1: 1, 2: 'ha!', 3: 3}
...
How to get hosting Activity from a view?
...
I just pulled that source code from the MediaRouter in the official support library and so far it works fine:
private Activity getActivity() {
Context context = getContext();
while (context instanceof ContextWrapper) {
if (context instance...
How to download and save a file from Internet using Java?
...m fos = new FileOutputStream("information.html");
fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
Using transferFrom() is potentially much more efficient than a simple loop that reads from the source channel and writes to this channel. Many operating systems can transfer bytes directly from...
How to find where a method is defined at runtime?
...dities in Rails' library loading, it only occurred when we ran it directly from Mongrel in production mode.
10 Answers
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Why are elementwise additions much faster in separate loops than in a combined loop?
...ch large allocations are requested, the allocator will request fresh pages from the OS. Therefore, there is a high chance that large allocations will appear at the same offset from a page-boundary.
Here's the test code:
int main(){
const int n = 100000;
#ifdef ALLOCATE_SEPERATE
double *a1 =...
Reload Flask app when template file changes
... need the application to restart to be refreshed, as they should be loaded from disk everytime render_template() is called. Maybe your templates are used differently though.
To reload your application when the templates change (or any other file), you can pass the extra_files argument to Flask().ru...
How do I remove the old history from a git repository?
...
Quoted from the linked wiki page on grafts. "As of Git 1.6.5, the more flexible git replace has been added, which allows you to replace any object with any other object, and tracks the associations via refs which can be pushed and p...
When is SQLiteOpenHelper onCreate() / onUpgrade() run?
...pplication. Use the application manager or adb uninstall your.package.name from the shell.
Clear application data. Use the application manager.
Increment the database version so that onUpgrade() is invoked. This is slightly more complicated as more code is needed.
For development time schema upgr...
How to get parameters from the URL with JSP
In JSP how do I get parameters from the URL?
9 Answers
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