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How to print a groupby object
...like a bug to me. I created an issue.
But a groupby operation doesn't actually return a DataFrame sorted by group. The .head() method is a little misleading here -- it's just a convenience feature to let you re-examine the object (in this case, df) that you grouped. The result of groupby is separat...
Insert, on duplicate update in PostgreSQL?
...it would be much slower, because each upsert would be its' own individual call into the database.
– baash05
Mar 1 '12 at 0:27
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How do I print the full value of a long string in gdb?
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As long as your program's in a sane state, you can also call (void)puts(your_string) to print it to stdout. Same principle applies to all functions available to the debugger, actually.
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Why does HTML5 form-validation allow emails without a dot?
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I wonder when the last time someone actually sent an email to localhost!
– Matthew Lock
May 19 '17 at 3:14
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How to quickly check if folder is empty (.NET)?
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There is a new feature in Directory and DirectoryInfo in .NET 4 that allows them to return an IEnumerable instead of an array, and start returning results before reading all the directory contents.
What's New in the BCL in .NET 4 Beta 1
Directory.EnumerateFileSystemEntries method overloads
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Determine if Python is running inside virtualenv
...r sys.base_prefix did not ever exist. So a fully robust check that handles all of these cases could look like this:
import sys
def get_base_prefix_compat():
"""Get base/real prefix, or sys.prefix if there is none."""
return getattr(sys, "base_prefix", None) or getattr(sys, "real_prefix", No...
Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
...it works. I figured the packets were some attempt at a hand-shake. So basically, I solved it using Google, patience and futzing around with the board!
– hoipolloi
Jan 12 '14 at 18:16
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How do I use extern to share variables between source files?
...ler is informed that a
variable exists (and this is its type); it does not allocate the
storage for the variable at that point.
A variable is defined when the compiler allocates the storage for
the variable.
You may declare a variable multiple times (though once is sufficient);
you may only defin...
Creating C formatted strings (not printing them)
...ee snprintf for a safer version).
A terminating null character is automatically appended after the
content.
After the format parameter, the function expects at least as many
additional arguments as needed for format.
Parameters:
str
Pointer to a buffer where the resulting C-string is stored. The ...
Load multiple packages at once
...t retyping the require command over and over? I've tried three approaches all of which crash and burn.
10 Answers
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