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pandas: multiple conditions while indexing data frame - unexpected behavior
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You can use query(), i.e.:
df_filtered = df.query('a == 4 & b != 2')
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Convert SQLITE SQL dump file to POSTGRESQL
...made constraint such as this:
CREATE TABLE tablename (
...
unsigned_column_name integer CHECK (unsigned_column_name > 0)
);
While SQLite defaults null values to '', PostgreSQL requires them to be set as NULL.
The syntax in the SQLite dump file appears to be mostly compatible with Postgre...
How to define an enumerated type (enum) in C?
...one like this:
enum strategy {RANDOM, IMMEDIATE, SEARCH};
enum strategy my_strategy = IMMEDIATE;
However, you can use a typedef to shorten the variable declarations, like so:
typedef enum {RANDOM, IMMEDIATE, SEARCH} strategy;
strategy my_strategy = IMMEDIATE;
Having a naming convention to dist...
Is there a way to make R beep/play a sound at the end of a script?
...eat to call it if the code crashes... Cheers!
– dez93_2000
Sep 2 '14 at 22:09
4
Sure! You just ha...
Difference between this and self in self-type annotations?
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btw you can also do _: B => for the non-alias case for simplicity
– Creos
Jun 19 '19 at 17:29
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Can I bind an array to an IN() condition?
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<?php
$ids = array(1, 2, 3, 7, 8, 9);
$inQuery = implode(',', array_fill(0, count($ids), '?'));
$db = new PDO(...);
$stmt = $db->prepare(
'SELECT *
FROM table
WHERE id IN(' . $inQuery . ')'
);
// bindvalue is 1-indexed, so $k+1
foreach ($ids as $k => $id)
$stmt->...
How do I strip non alphanumeric characters from a string and keep spaces?
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Add spaces to the negated character group:
@search_query = @search_query.gsub(/[^0-9a-z ]/i, '')
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CSS Display an Image Resized and Cropped
... of examples on css3.info.
Implemented based on your example, using donald_duck_4.jpg. In this case, background-size: cover; is just what you want - it fits the background-image to cover the entire area of the containing <div> and clips the excess (depending on the ratio).
.with-bg-size ...
SVN encrypted password store
... provide for hashed pw like htpasswd or similar.
– d-_-b
Sep 21 '11 at 6:41
17
@sims Hashing is g...
Excluding directories in os.walk
...ld a comprehension only for its side effects...
– 301_Moved_Permanently
Nov 5 '16 at 9:33
3
This ...