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Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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How to pull a random record using Django's ORM?
...['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
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How can I debug git/git-shell related problems?
...SS=2 GIT_TRACE_PACKET=2 GIT_TRACE_PACKFILE=2 GIT_TRACE_SETUP=2 GIT_TRACE_SHALLOW=2 git pull origin master -v -v; set +x
– Paul Irish
Jan 9 '16 at 21:22
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How to convert ActiveRecord results into an array of hashes
...d objects to Ruby Hashes despite its name
tasks_records = TaskStoreStatus.all
tasks_records = tasks_records.as_json
# You can now add new records and return the result as json by calling `to_json`
tasks_records << TaskStoreStatus.last.as_json
tasks_records << { :task_id => 10, :sto...
Constructors in JavaScript objects
...en mention Foo, while in the latter case it will know that it's Foo being called. Very helpful for debugging.
– Joachim Isaksson
Oct 21 '13 at 11:36
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What is the combinatory logic equivalent of intuitionistic type theory?
...------------ S ={beta} T
G |- x : S G |- s : T
In a small variation from the original, I've made lambda the only binding operator, so the second argument of Pi should be a function computing the way the return type depends on the input. By convention (e.g. in Agda, but sadly not...
How do I concatenate or merge arrays in Swift?
...ith Sequence's flatMap(_:) method
Swift provides a flatMap(_:) method for all types that conform to Sequence protocol (including Array). flatMap(_:) has the following declaration:
Returns an array containing the concatenated results of calling the given transformation with each element of this ...
Is it possible to forward-declare a function in Python?
...rwards is impossible, what about defining it in some other module?
Technically you still define it first, but it's clean.
You could create a recursion like the following:
def foo():
bar()
def bar():
foo()
Python's functions are anonymous just like values are anonymous, yet they can be ...
How to change the type of a field?
...(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the field bad from a number to a string in collection foo.
db.foo.find( { 'bad' :...
Abort makefile if variable not set
... an auxiliary function for that:
# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
# 1. Variable name(s) to test.
# 2. (optional) Error message to print.
check_defined = \
$(strip $(foreach 1,$1, \
$(call __check_defined,$...