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How to drop rows of Pandas DataFrame whose value in a certain column is NaN
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edited Feb 16 at 7:46
AMC
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answered Nov 16...
How can I get a list of locally installed Python modules?
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624
+100
Solution...
Is the sizeof(some pointer) always equal to four?
For example:
sizeof(char*) returns 4. As does int* , long long* , everything that I've tried. Are there any exceptions to this?
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Unexpected results when working with very big integers on interpreted languages
...supports arbitrary precision. It will produce the correct answer on 32 or 64 bit platforms.
This can be seen by raising 2 to a power far greater than the bit width of the platform:
>>> 2**99
633825300114114700748351602688L
You can demonstrate (with Python) that the erroneous values you...
How do you print out a stack trace to the console/log in Cocoa?
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547
NSLog(@"%@",[NSThread callStackSymbols]);
This code works on any thread.
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Changing Vim indentation behavior by file type
...ould indent with 2 spaces, but if I open a Powershell script it should use 4 spaces.
11 Answers
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Swapping column values in MySQL
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204
I just had to deal with the same and I'll summarize my findings.
The UPDATE table SET X=Y, Y=X...
I need to store postal codes in a database. How big should the column be?
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answered Nov 28 '08 at 4:19
stragerstrager
81.9k2323 gold badges125125 silver badges171171 bronze badges
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Having both a Created and Last Updated timestamp columns in MySQL 4.0
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edited Apr 21 '14 at 15:19
kingjeffrey
13k55 gold badges3838 silver badges4747 bronze badges
a...
PHP Regex to check date is in YYYY-MM-DD format
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Try this.
$date="2012-09-12";
if (preg_match("/^[0-9]{4}-(0[1-9]|1[0-2])-(0[1-9]|[1-2][0-9]|3[0-1])$/",$date)) {
return true;
} else {
return false;
}
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