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How can I check whether an array is null / empty?
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218
There's a key difference between a null array and an empty array. This is a test for null.
in...
Efficient way to remove keys with empty strings from a dict
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Python 2.X
dict((k, v) for k, v in metadata.iteritems() if v)
Python 2.7 - 3.X
{k: v for k, v in metadata.items() if v is not None}
Note that all of your keys have values. It's just that some of those values are the empty s...
What is a Python equivalent of PHP's var_dump()? [duplicate]
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287
To display a value nicely, you can use the pprint module. The easiest way to dump all variable...
Read an Excel file directly from a R script
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12 Answers
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用户界面（UI）组件 · App Inventor 2 中文网
...如何水平对齐的数字，含义如下：
1 （左对齐）
2 （右对齐）
3 （水平居中）
垂直对齐
表示屏幕内容如何垂直对齐的数字，含义如下：
1 （顶部对齐）
2 （垂直居中）
3 （底部对齐）
如果屏幕可...
Print PHP Call Stack
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126
If you want to generate a backtrace, you are looking for debug_backtrace and/or debug_print_bac...
AutoMapper: “Ignore the rest”?
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Can GencerCan Gencer
8,27955 gold badges2828 silver badges5151 bronze badges
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Accessing inactive union member and undefined behavior?
...ough a union, whereas C++ (c++11) has no such permission.
c11
6.5.2.3 Structure and union members
95) If the member used to read the contents of a union object is not the same as the member last used to
store a value in the object, the appropriate part of the object representation of...
Selenium: FirefoxProfile exception Can't load the profile
Per this previous question I updated Selenium to version 2.0.1
But now I have another error, even when the profile files exist under /tmp/webdriver-py-profilecopy :
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