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Pandas percentage of total with groupby
... is a table of some kind, so 100 * x doesn't intuitively make sense (especially when some of the cells contain strings like AZ, ...).
– dhardy
Feb 6 '15 at 9:42
6
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What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
... platforms, memory leaks are often caused by unreleased pointers. Traditionally, it has always been of utmost importance to check your allocs, copies and retains to make sure each has a corresponding release message.
...
Convert a python 'type' object to a string
...
print type(someObject).__name__
If that doesn't suit you, use this:
print some_instance.__class__.__name__
Example:
class A:
pass
print type(A())
# prints <type 'instance'>
print A().__class__.__name__
# prints A
Also, it seems th...
Export and Import all MySQL databases at one time
I want to keep a backup of all my MySQL databases. I have more than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
...
How to include route handlers in multiple files in Express?
...
Actually, the author (TJ Holowaychuck) gives a better approche: vimeo.com/56166857
– avetisk
Mar 23 '13 at 9:36
...
Relative paths in Python
..., you want to do something like this:
import os
dirname = os.path.dirname(__file__)
filename = os.path.join(dirname, 'relative/path/to/file/you/want')
This will give you the absolute path to the file you're looking for. Note that if you're using setuptools, you should probably use its package re...
Why split the tag when writing it with document.write()?
...lt;script> and/or </script> tags up within document.write() calls?
5 Answers
...
iOS开发调试技巧总结 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...(format,...)do{\
fprintf(stderr,"%s\n",\
[[[NSStringstringWithUTF8String:__FILE__]lastPathComponent]UTF8String],\
__LINE__,__func__);\
(NSLog)((format),##__VA_ARGS__);\
fprintf(stderr,"-------\n");\
}while(0)
@interfaceViewController
@end
@implementationViewController
-(void)viewDi...
How to change field name in Django REST Framework
...get_alternate_name(self, obj):
return obj.alternate_name
Additionally, you can use serializers.CharField with source attribute:
class ParkSerializer(serializers.ModelSerializer):
location = serializers.CharField(source='other_fields')
class Meta:
model = Park
fiel...
How do I export UIImage array as a movie?
...riter has an input of type AVAssetWriterInput, which in turn has a method called appendSampleBuffer: that lets you add individual frames to a video stream. Essentially you’ll have to:
1) Wire the writer:
NSError *error = nil;
AVAssetWriter *videoWriter = [[AVAssetWriter alloc] initWithURL:
[...