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How to convert lazy sequence to non-lazy in Clojure
... to force the entire sequence for realized? to return true. E.g. (let [r (range) r? (realized? r)] (doall (take 1 r)) [r? (realized? r)]) => [false true]
– Alex Coventry
Apr 21 '14 at 17:45
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Performance of Java matrix math libraries? [closed]
...between Java libraries and while there is no clear winner across the whole range of operations, there are a few clear leaders as can be seen in the latest performance results (October 2013).
If you are working with "large" matrices and can use native libraries, then the clear winner (about 3.5x fas...
matplotlib colorbar for scatter
... you?
import matplotlib.pyplot as plt
cm = plt.cm.get_cmap('RdYlBu')
xy = range(20)
z = xy
sc = plt.scatter(xy, xy, c=z, vmin=0, vmax=20, s=35, cmap=cm)
plt.colorbar(sc)
plt.show()
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impro...
Function to Calculate Median in SQL Server
...le = 2
group by quartile
This will give you the median and interquartile range in one fell swoop. If you really only want one row that is the median then uncomment the where clause.
When you stick that into an explain plan, 60% of the work is sorting the data which is unavoidable when calculatin...
Python int to binary string?
...ef toBinary(n):
return ''.join(str(1 & int(n) >> i) for i in range(64)[::-1])
This function can convert a positive integer as large as 18446744073709551615, represented as string '1111111111111111111111111111111111111111111111111111111111111111'.
It can be modified to serve a much l...
Get day of week in SQL Server 2005/2008
... better solution:
MS SQL: Day of Week
The day of week will then be in the range 0 to 6, where 0 is Sunday, 1 is Monday, etc. Then you can use a simple case statement to return the correct weekday name.
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How to get the last element of a slice?
... I am not sure but I got panic: runtime error: index out of range for profiles[len(profiles)-1].UserId, I guess the length of the slice is 0 so it panics?
– tom10271
Aug 16 '19 at 2:20
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hexadecimal string to byte array in python
...e binary data using something like:
data = "fef0babe"
bits = ""
for x in xrange(0, len(data), 2)
bits += chr(int(data[x:x+2], 16))
This is probably not the fastest way (many string appends), but quite simple using only core Python.
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Random row from Linq to Sql
... this answer here as a potential point of interest for LINQ to Objects.
Strangely enough, you don't actually need to get the count. You do, however, need to fetch every element unless you get the count.
What you can do is keep the idea of a "current" value and the current count. When you fetch the...
Preferred Java way to ping an HTTP URL for availability
...s <code>true</code> if the response code is in
* the 200-399 range.
* @param url The HTTP URL to be pinged.
* @param timeout The timeout in millis for both the connection timeout and the response read timeout. Note that
* the total timeout is effectively two times the given timeout....