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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...
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...
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...
AutoMapper: “Ignore the rest”?
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Can GencerCan Gencer
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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...
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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Bash if statement with multiple conditions throws an error
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251
Use -a (for and) and -o (for or) operations.
tldp.org/LDP/Bash-Beginners-Guide/html/sect_07_0...
Replace only text inside a div using jquery
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edited Oct 29 '14 at 20:50
cuSK
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answered Aug 8 '1...
Assign pandas dataframe column dtypes
...ated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}, 'y': {0: '1', 1: '2'}, 'z': {0: '2018-05-01', 1: '2018-05-02'}})
df.dtypes
x object
y object
z object
dtype: object
df
x y z
0 a 1 2018-05-01
1 b 2 2018-05-02
You can apply these to each column you want to co...