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What is the use of the ArraySegment class?
...l array, get the first item, and so on:
var array = new byte[] { 5, 8, 9, 20, 70, 44, 2, 4 };
array.Dump();
var segment = new ArraySegment<byte>(array, 2, 3);
segment.Dump(); // output: 9, 20, 70
segment.Reverse().Dump(); // output 70, 20, 9
segment.Any(s => s == 99).Dump(); // output fals...
Pandas DataFrame Groupby two columns and get counts
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126
Followed by @Andy's answer, you can do following to solve your second question:
In [56]: df.gr...
CALayer with transparent hole in it
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219
I was able to solve this with Jon Steinmetz suggestion. If any one cares, here's the final sol...
How to remove all leading zeroes in a string
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answered Feb 23 '11 at 23:36
lonesomedaylonesomeday
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What exactly do “u” and “r” string flags do, and what are raw string literals?
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702
There's not really any "raw string"; there are raw string literals, which are exactly the string...
Convert a PHP object to an associative array
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32 Answers
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How do I find where an exception was thrown in C++?
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72
Here's some info that may be of use in debugging your problem
If an exception is uncaught, the s...
cartesian product in pandas
...rom pandas import DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6...
surface plots in matplotlib
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122
For surfaces it's a bit different than a list of 3-tuples, you should pass in a grid for the do...