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Strings in a DataFrame, but dtype is object
...ll me that I have objects, although every item in the selected column is a string — even after explicit conversion.
4 Ans...
Rails 3: Get Random Record
...ect_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+------+---------------+------+---------+------+--------+---------------------------------+
| 1 | SIMPLE | users | ALL | NULL | NULL | NULL | NUL...
What is the difference between NULL, '\0' and 0?
... with pointers. However you may see something similar to this code:
if (!*string_pointer)
checks if the string pointer is pointing at a null character
if (*string_pointer)
checks if the string pointer is pointing at a non-null character
Don't get these confused with null pointers. Just becaus...
Reading/writing an INI file
...t more difficult. (I'm looking at you, database "providers" and connection strings.) So INI files are also generally better for non-manual editing, as well.
– jpmc26
Mar 16 '17 at 2:51
...
How do I do an OR filter in a Django query?
...item.moderated = False)
(edit - I was initially unsure if this caused an extra query but @spookylukey pointed out that lazy queryset evaluation takes care of that)
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How to retrieve form values from HTTPPOST, dictionary or?
...
@Goose, because it is magic strings. You don't get any compile time safety. Your code will fail at runtime if you make a typo in the name of the variable whereas if you are using strong typing, the compiler will be your friend.
– D...
Should a return statement be inside or outside a lock?
...e of the try/finally - however, the return outside the lock still requires extra locals which can't be optimised away - and takes more code...
– Marc Gravell♦
Nov 5 '08 at 21:18
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Why don't Java's +=, -=, *=, /= compound assignment operators require casting?
...57
or
byte b = 100;
b /= 2.5;
System.out.println(b); // prints 40
or
char ch = '0';
ch *= 1.1;
System.out.println(ch); // prints '4'
or
char ch = 'A';
ch *= 1.5;
System.out.println(ch); // prints 'a'
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Breakpoint on property change
... Best solution for anyone trying to debug from dev console. No extra effort to reuse on any website, awesome!
– Chris Hayes
Jul 29 at 21:16
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...
Setting Vim whitespace preferences by filetype
...local ts=4 sw=4 sts=0 noexpandtab
Also note:
You can make vim show tab characters by using :set list.
Once you have the tab/space options set correctly, you can make vim repair the file (replace spaces with tabs or vice versa) using the :retab! command.
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