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Group By Multiple Columns
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Use an anonymous type.
Eg
group x by new { x.Column1, x.Column2 }
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Replacements for switch statement in Python?
I want to write a function in Python that returns different fixed values based on the value of an input index.
44 Answers...
SQL is null and = null [duplicate]
...t on rows by coding where my_column = null.
SQL provides the special syntax for testing if a column is null, via is null and is not null, which is a special condition to test for a null (or not a null).
Here's some SQL showing a variety of conditions and and their effect as per above.
create tabl...
Standardize data columns in R
I have a dataset called spam which contains 58 columns and approximately 3500 rows of data related to spam messages.
15 ...
How to remove all whitespace from a string?
So " xx yy 11 22 33 " will become "xxyy112233" . How can I achieve this?
9 Answers
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How to check if all elements of a list matches a condition?
...which is the builtin for this situation. We combine this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
>>> all(flag == 0 for (_, _, flag) in items)
True
>>> items = [[1, 2, 0]...
Suppress/ print without b' prefix for bytes in Python 3
... is to manually slice off the b'' from the resulting repr():
>>> x = b'\x01\x02\x03\x04'
>>> print(repr(x))
b'\x01\x02\x03\x04'
>>> print(repr(x)[2:-1])
\x01\x02\x03\x04
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Is there a numpy builtin to reject outliers from a list
...a)] TypeError: only integer scalar arrays can be converted to a scalar index OR it just freezes my program
– john ktejik
Sep 16 '17 at 22:26
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Double Iteration in List Comprehension
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I hope this helps someone else since a,b,x,y don't have much meaning to me! Suppose you have a text full of sentences and you want an array of words.
# Without list comprehension
list_of_words = []
for sentence in text:
for word in sentence:
list_of_word...
Are PHP Variables passed by value or by reference?
...he argument name in the function definition.
<?php
function add_some_extra(&$string)
{
$string .= 'and something extra.';
}
$str = 'This is a string, ';
add_some_extra($str);
echo $str; // outputs 'This is a string, and something extra.'
?>
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