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Breadth First Vs Depth First
When Traversing a Tree/Graph what is the difference between Breadth First and Depth first? Any coding or pseudocode examples would be great.
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Is there a NumPy function to return the first index of something in an array?
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Yes, here is the answer given a NumPy array, array, and a value, item, to search for:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your it...
Formatting floats without trailing zeros
...t formatting rather than scientific notation, etc etc. Yeah, not as slick and elegant as %g, but, it works (and I don't know how to force %g to never use scientific notation;-).
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Counting null and non-null values in a single query
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This works for Oracle and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) fro...
Understanding Python's “is” operator
...e value.
From the documentation for the is operator:
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object.
Use the == operator instead:
print(x == y)
This prints True. x and y are two separate lists:
x[0] = 4
print(y) # prints [1...
Closing multiple issues in Github with a commit message
...rest of commit message.
The closes clauses can be anywhere in the message and fixes is a valid synonym:
This fixes a memory leak in foo() that closes #4,
also fixes #5 which is a duplicate.
The following used to work, but nowadays only references issues #2 and #3.
Closes #1, #2, #3
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jQuery slide left and show
I extended the jQuery effects called slideRightShow() and slideLeftHide() with a couple functions that work similarly to slideUp() and slideDown() as seen below. However, I would also like to implement slideLeftShow() and slideRightHide() .
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How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fact 0 = 1
fact n =...
Converting bytes to megabytes
... it is not correct actually because mega means 1 000 000. There is a new standard name for 220 bytes, it is mebibyte (http://en.wikipedia.org/wiki/Mebibyte) and it gathers popularity.
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Google maps API V3 - multiple markers on exact same spot
Bit stuck on this one. I am retrieving a list of geo coords via JSON and popping them onto a google map. All is working well except in the instance when I have two or more markers on the exact same spot. The API only displays 1 marker - the top one. This is fair enough I suppose but would like t...