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How to delete multiple values from a vector?
I have a vector like: a = c(1:10) and I need to remove multiple values, like: 2, 3, 5
8 Answers
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SQL Server 2008: How to query all databases sizes?
I have MS SQL 2008 R2, 500 databases.
What is the most efficient, easiest and 'modern' way to query all databases sizes.
14...
SQLAlchemy: how to filter date field?
...our filter is excluding all records: you should change the <= for >= and vice versa:
qry = DBSession.query(User).filter(
and_(User.birthday <= '1988-01-17', User.birthday >= '1985-01-17'))
# or same:
qry = DBSession.query(User).filter(User.birthday <= '1988-01-17').\
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How to convert all text to lowercase in Vim
...rocessor). If you want to convert text to lowercase, create a visual block and press u (or U to convert to uppercase). Tilde (~) in command mode reverses case of the character under the cursor.
If you want to see all text in Vim in small caps, you might want to look at the guifont option, or type :s...
Reset the database (purge all), then seed a database
Is there a rake command to wipe out the data in the database tables?
6 Answers
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ERROR 1452: Cannot add or update a child row: a foreign key constraint fails
...relationships involve a parent table that holds the
central data values, and a child table with identical values pointing
back to its parent. The FOREIGN KEY clause is specified in the child
table.
It will reject any INSERT or UPDATE operation that attempts to create
a foreign key value...
What is the proper way to format a multi-line dict in Python?
...uld use a similar but not identical format as your format 3. Here is mine, and why.
my_dictionary = { # Don't think dict(...) notation has more readability
"key1": 1, # Indent by one press of TAB (i.e. 4 spaces)
"key2": 2, # Same indentation scale as above
"key3": 3, # Keep this final c...
Does MongoDB's $in clause guarantee order
...the results
{ "$sort": { "weight": 1 } }
])
So that would be the expanded form. What basically happens here is that just as the array of values is passed to $in you also construct a "nested" $cond statement to test the values and assign an appropriate weight. As that "weight" value reflects t...
How can I create a copy of an object in Python?
... you can use the copy.deepcopy() function.
For more details about shallow and deep copying please refer to the other answers to this question and the nice explanation in this answer to a related question.
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Sorting an array of objects by property values
I've got the following objects using AJAX and stored them in an array:
30 Answers
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