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Creating a zero-filled pandas data frame
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140
You can try this:
d = pd.DataFrame(0, index=np.arange(len(data)), columns=feature_list)
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Alternatives to gprof [closed]
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answered Dec 19 '09 at 5:26
Norman RamseyNorman Ramsey
184k5757 gold badges336336 silver badges517517 bronze badges
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Why are hexadecimal numbers prefixed with 0x?
Why are hexadecimal numbers prefixed as 0x ?
I understand the usage of the prefix but I don't understand the significance of why 0x was chosen.
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Any shortcut to initialize all array elements to zero?
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A default value of 0 for arrays of integral types is guaranteed by the language spec:
Each class variable, instance variable, or array component is initialized with a default value when it is created (§15.9, §15.10) [...] For type int, th...
Detecting a mobile browser
...opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows ce|xda|xiino/i.test(a)||/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|...
How do Python's any and all functions work?
...or example,
>>> multiples_of_6 = (not (i % 6) for i in range(1, 10))
>>> any(multiples_of_6)
True
>>> list(multiples_of_6)
[False, False, False]
Here, (not (i % 6) for i in range(1, 10)) is a generator expression which returns True if the current number within 1 and 9 i...
Appropriate datatype for holding percent values?
What is the best datatype for holding percent values ranging from 0.00% to 100.00%?
5 Answers
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How to calculate the difference between two dates using PHP?
...rom this it's rather easy to calculate different time periods.
$date1 = "2007-03-24";
$date2 = "2009-06-26";
$diff = abs(strtotime($date2) - strtotime($date1));
$years = floor($diff / (365*60*60*24));
$months = floor(($diff - $years * 365*60*60*24) / (30*60*60*24));
$days = floor(($diff - $years ...
Simplest code for array intersection in javascript
... Ry-♦
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answered Dec 11 '09 at 3:08
Anon.Anon.
49.5k88 gold badges...
what is faster: in_array or isset? [closed]
...t-in function.
These can be demonstrated by using an array with values (10,000 in the test below), forcing in_array to do more searching.
isset: 0.009623
in_array: 1.738441
This builds on Jason's benchmark by filling in some random values and occasionally finding a value that exists in the a...