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Is there a method to generate a UUID with go language
...the purpose ?
These lines clamp the values of byte 6 and 8 to a specific range. rand.Read returns random bytes in the range 0-255, which are not all valid values for a UUID. As far as I can tell, this should be done for all the values in the slice though.
If you are on linux, you can alternativel...
Unicode characters in URLs
... Domain names have nothing to do with this. All browsers disallow a wide range of characters to prevent phishing. Displaying non-ASCII characters in the path or query string part does not create a similar vilnerability. IE simply didn't bother to implement it. (And Firefox is the only one that imp...
Reading a huge .csv file
....csv files in Python 2.7 with up to 1 million rows, and 200 columns (files range from 100mb to 1.6gb). I can do this (very slowly) for the files with under 300,000 rows, but once I go above that I get memory errors. My code looks like this:
...
Statistics: combinations in Python
...ion
def nCk(n,k):
return int( reduce(mul, (Fraction(n-i, i+1) for i in range(k)), 1) )
Test - printing Pascal's triangle:
>>> for n in range(17):
... print ' '.join('%5d'%nCk(n,k) for k in range(n+1)).center(100)
...
1 ...
Fast way of counting non-zero bits in positive integer
...You can generate it at runtime:
counts = bytes(bin(x).count("1") for x in range(256)) # py2: use bytearray
Or just define it literally:
counts = (b'\x00\x01\x01\x02\x01\x02\x02\x03\x01\x02\x02\x03\x02\x03\x03\x04'
b'\x01\x02\x02\x03\x02\x03\x03\x04\x02\x03\x03\x04\x03\x04\x04\x05'
...
Return empty cell from formula in Excel
...'re going to have to use VBA, then. You'll iterate over the cells in your range, test the condition, and delete the contents if they match.
Something like:
For Each cell in SomeRange
If (cell.value = SomeTest) Then cell.ClearContents
Next
...
How do I generate random number for each row in a TSQL Select?
...with a uniform distribution:
ABS(CHECKSUM(NewId())) % 14
To change your range, just change the number at the end of the expression. Be extra careful if you need a range that includes both positive and negative numbers. If you do it wrong, it's possible to double-count the number 0.
A small warni...
Shuffling a list of objects
...where the objects are lists:
from random import shuffle
x = [[i] for i in range(10)]
shuffle(x)
# print(x) gives [[9], [2], [7], [0], [4], [5], [3], [1], [8], [6]]
# of course your results will vary
Note that shuffle works in place, and returns None.
...
How to plot two histograms together in R?
...SE)
histCucumber <- hist(cucumberLengths,plot = FALSE)
## calculate the range of the graph
xlim <- range(histCucumber$breaks,histCarrot$breaks)
ylim <- range(0,histCucumber$density,
histCarrot$density)
## plot the first graph
plot(histCarrot,xlim = xlim, ylim = ylim,
col ...
Multiple linear regression in Python
...= linear_model.LinearRegression()
clf.fit([[getattr(t, 'x%d' % i) for i in range(1, 8)] for t in texts],
[t.y for t in texts])
Then clf.coef_ will have the regression coefficients.
sklearn.linear_model also has similar interfaces to do various kinds of regularizations on the regression.
...