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JavaScript: empty array, [ ] evaluates to true in conditional structures. Why is this?
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From http://www.sitepoint.com/javascript-truthy-falsy/
The following values are always falsy:
false
0 (zero)
"" (empty string)
null
undefined
NaN (a special Number value meaning Not-a-Number!)
All other values are truthy...
How to control the line spacing in UILabel
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Starting from iOS 6 you can set an attributed string to the UILabel. Check the following :
NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:label.text];
NSMutableParagraphStyle *paragra...
How to skip over an element in .map()?
...;
}
return result;
}, []);
In that version, the code in the .filter() from the first sample is part of the .reduce() callback. The image source is only pushed onto the result array in the case where the filter operation would have kept it.
update — This question gets a lot of attention, and I...
How to store a dataframe using Pandas
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@user1700890 try to generate from random data (text and arrays) and post a new question. I don't think this can be right/suspect we're missing something. New question will get more eyes, but try to include/generate a DataFrame that reproduces :)
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force Maven to copy dependencies into target/lib
...n will generate a complete JAR file with all your classes plus the classes from any dependencies.
If you want to simply pull your dependencies into the target directory interactively, then use the dependency plugin to copy your files in.
If you want to pull in the dependencies for some other type of...
Why use ICollection and not IEnumerable or List on many-many/one-many relationships?
... for a full list: http://msdn.microsoft.com/en-us/library/6sh2ey19.aspx).
From a more specific standpoint, lazy loading comes in to play with choosing the type. By default, navigation properties in Entity Framework come with change tracking and are proxies. In order for the dynamic proxy to be crea...
搭建高可用mongodb集群（二）—— 副本集 - 大数据 & AI - 清泛网 - 专注C/...
...ec 29 20:12:02.953 [rsStart] replSet can't get local.system.replset config from self or any seed (EMPTYCONFIG)
Sun Dec 29 20:12:02.953 [rsStart] replSet info you may need to run replSetInitiate -- rs.initiate() in the shell -- if that is not already done
5、初始化副本集
在三台机器...
How to test multiple variables against a value?
... x, y and z could change, so either solution needs to build a tuple or set from scratch, and I suspect whatever lookup savings you might get when checking for membership would be swamped by greater set creation time.
– ShadowRanger
Sep 4 '16 at 0:37
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matplotlib Legend Markers Only Once
...goal I simply use somthing like that at the beginning of my python files.
from pylab import *
rcParams['legend.numpoints'] = 1
This will apply to all plots generated from my python file.
EDIT: For those who do not like to import pylab, the long answer is
import matplotlib as mpl
mpl.rcParams['l...
Splitting on last delimiter in Python string?
...;> s.rpartition(',')
('a,b,c', ',', 'd')
Both methods start splitting from the right-hand-side of the string; by giving str.rsplit() a maximum as the second argument, you get to split just the right-hand-most occurrences.
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