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Django South - table already exists
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Although the table "myapp_tablename" already exists error stop raising
after I did ./manage.py migrate myapp --fake, the DatabaseError shows
no such column: myapp_mymodel.added_field.
Got exactly the same problem!
1.Firstly check the migration...
What does it mean for a data structure to be “intrusive”?
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boost.org/doc/libs/1_45_0/doc/html/intrusive.html has examples and a good description of pros and cons.
– Tony Delroy
Feb 16 '11 at 6:37
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Can I query MongoDB ObjectId by date?
...cuments created after midnight on May 25th, 1980 */
db.mycollection.find({ _id: { $gt: objectIdWithTimestamp('1980/05/25') } });
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How do you remove duplicates from a list whilst preserving order?
.../uniqifiers-benchmark
Fastest one:
def f7(seq):
seen = set()
seen_add = seen.add
return [x for x in seq if not (x in seen or seen_add(x))]
Why assign seen.add to seen_add instead of just calling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more cos...
How do PHP sessions work? (not “how are they used?”)
...on files are usually stored in, say, /tmp/ on the server, and named sess_{session_id} . I have been looking at the contents and cannot figure out how they really work.
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How do you test functions and closures for equality?
...uence language design, so without a quick fix like the now deprecated @objc_block in matt's answer, I would argue that Swift can't properly store and retrieve closures at this time. So I don't think it's appropriate to advocate the use of Swift in callback heavy code like the kind encountered in we...
Remove the legend on a matplotlib figure
....0rc4, a remove method has been added to the legend object.
Usage:
ax.get_legend().remove()
or
legend = ax.legend(...)
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legend.remove()
See here for the commit where this was introduced.
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Changing every value in a hash in Ruby
...ring objects):
# Two ways to achieve the same result (any Ruby version)
my_hash.each{ |_,str| str.gsub! /^|$/, '%' }
my_hash.each{ |_,str| str.replace "%#{str}%" }
If you want the hash to change in place, but you don't want to affect the strings (you want it to get new strings):
# Two ways to ac...
iOS 7 style Blur view
...[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[_toolbar]|"
options:0
metrics:0
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get list from pandas dataframe column
...hon list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataFrame:\n{df}\n")
print(f"column types:\n{df.dtyp...