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Scaling Node.js
...like to know what the general principles are for scaling node up to, say, 20 queries per second.
1 Answer
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Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
When passing argument to main() in a C or C++ application, will argv[0] always be the name of the executable? Or is this just a common convention and not guaranteed to be true 100% of the time?
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adding noise to a signal in python
I want to add some random noise to some 100 bin signal that I am simulating in Python - to make it more realistic.
7 Answer...
How to append rows to an R data frame
...sive insight than system.time:
library(microbenchmark)
microbenchmark(f1(1000), f3(1000), f4(1000), times = 5)
# Unit: milliseconds
# expr min lq median uq max neval
# f1(1000) 1024.539618 1029.693877 1045.972666 1055.25931 1112.769176 5
# f3(1000) ...
Difference between decimal, float and double in .NET?
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2310
float and double are floating binary point types. In other words, they represent a number like t...
Get path of executable
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edited Nov 20 '17 at 6:57
James Mart
42033 silver badges1313 bronze badges
answered Oct 6 ...
How is a CRC32 checksum calculated?
...e polynomial for CRC32 is:
x32 + x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 + x7 + x5 + x4 + x2 + x + 1
Wikipedia
CRC calculation
Or in hex and binary:
0x 01 04 C1 1D B7
1 0000 0100 1100 0001 0001 1101 1011 0111
The highest term (x32) is usually not explicitly written, so it can i...
How do you get the width and height of a multi-dimensional array?
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answered Nov 23 '10 at 19:52
Reed CopseyReed Copsey
509k6868 gold badges10671067 silver badges13241324 bronze badges
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Getting the first character of a string with $str[0]
I want to get the first letter of a string and I've noticed that $str[0] works great. I am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right –...
How to read a .xlsx file using the pandas Library in iPython?
... for sheet_name in xl_file.sheet_names}
Update: In pandas version 0.21.0+ you will get this behavior more cleanly by passing sheet_name=None to read_excel:
dfs = pd.read_excel(file_name, sheet_name=None)
In 0.20 and prior, this was sheetname rather than sheet_name (this is now deprecat...