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Efficient way to apply multiple filters to pandas DataFrame or Series
...f_2 = df["a"] >= 0etc. No need for that function... (nice use of higher order function though...)
– A. Rabus
Aug 29 '19 at 8:29
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How do you serialize a model instance in Django?
...h trying to serialize a single object, not a list of objects. That way, in order to get rid of different hacks, just use Django's model_to_dict (if I'm not mistaken, serializers.serialize() relies on it, too):
from django.forms.models import model_to_dict
# assuming obj is your model instance
dic...
SQL Server - copy stored procedures from one db to another
...d supported by default
Cons: scripts might not be in the correct execution order and you might get errors if stored procedure already exists on secondary database. Make sure you review the script before executing.
Third party tools
Pros: tools such as ApexSQL Diff (this is what I use but there ...
How do I find out which keystore was used to sign an app?
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Highly active question. Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity.
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How to test if a string is basically an integer in quotes using Ruby
... String
def integer?
[ # In descending order of likeliness:
/^[-+]?[1-9]([0-9]*)?$/, # decimal
/^0[0-7]+$/, # octal
/^0x[0-9A-Fa-f]+$/, # hexadecimal
/^0b[01]+$/ # binary
].each do |match_pattern|...
What are bitwise shift (bit-shift) operators and how do they work?
...substitute shifts for multiplications when possible. What? Bitshifts are orders of magnitude faster when it comes down to the low level operations of a CPU, a good optimizing compiler would do the exact opposite, that is, turning ordinary multiplications by powers of two into bit shifts.
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How do I create a link using javascript?
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In order to avoid XSS, you should avoid string concatenation (+) and .innerHTML when building HTML. With jQuery, .attr("href", desiredLink) and .text(desiredText) are what you want here.
– Wes Turner
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Is there a setting on Google Analytics to suppress use of cookies for users who have not yet given c
... asking whether you are willing to accept them, 2) it must set a cookie in order to save your cookie preferences, and 3) it states that the site will not control 3rd party cookies, which is in direct violation of the spirit if not the letter of the EU directive. I suspect that the Beebs will get sm...
What are the differences between numpy arrays and matrices? Which one should I use?
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ERROR: Error 1005: Can't create table (errno: 121)
...ts
WHERE
constraint_type = 'FOREIGN KEY'
AND table_schema = DATABASE()
ORDER BY
constraint_name;
Look for more information there, or try to see where the error occurs. Looks like a problem with a foreign key to me.
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