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What do you call the -> operator in Ruby?
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240
In Ruby Programming Language ("Methods, Procs, Lambdas, and Closures"), a lambda defined using...
how do you filter pandas dataframes by multiple columns
... sub-statements with ():
males = df[(df[Gender]=='Male') & (df[Year]==2014)]
To store your dataframes in a dict using a for loop:
from collections import defaultdict
dic={}
for g in ['male', 'female']:
dic[g]=defaultdict(dict)
for y in [2013, 2014]:
dic[g][y]=df[(df[Gender]==g) &...
Changing the size of a column referenced by a schema-bound view in SQL Server
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edited Aug 24 '09 at 6:03
answered Aug 24 '09 at 2:02
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How can I filter a Django query with a list of values?
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562
From the Django documentation:
Blog.objects.filter(pk__in=[1, 4, 7])
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How to change the foreign key referential action? (behavior)
...ocess:
Suppose, a table1 has a foreign key with column name fk_table2_id, with constraint name fk_name and table2 is referred table with key t2 (something like below in my diagram).
table1 [ fk_table2_id ] --> table2 [t2]
First step, DROP old CONSTRAINT: (reference)
ALTER TABLE ...
Order data frame rows according to vector with specific order
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236
Try match:
df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2)))
targe...
Appending to an empty DataFrame in Pandas?
... pd.DataFrame({"A": range(3)})
>>> df.append(data)
A
0 0
1 1
2 2
But the append doesn't happen in-place, so you'll have to store the output if you want it:
>>> df
Empty DataFrame
Columns: []
Index: []
>>> df = df.append(data)
>>> df
A
0 0
1 1
2 2
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ViewParam vs @ManagedProperty(value = “#{param.id}”)
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2 Answers
2
Active
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What is the maximum number of characters that nvarchar(MAX) will hold?
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Max. capacity is 2 gigabytes of space - so you're looking at just over 1 billion 2-byte characters that will fit into a NVARCHAR(MAX) field.
Using the other answer's more detailed numbers, you should be able to store
(2 ^ 31 - 1 - 2) / 2 = ...
How do you exit from a void function in C++?
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200
Use a return statement!
return;
or
if (condition) return;
You don't need to (and can't) ...