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Reading output of a command into an array in Bash
...=$'\n' read -r -d '' -a my_array < <( my_command && printf '\0' )
Please make sure you use exactly this form, i.e., make sure you have the following:
IFS=$'\n' on the same line as the read statement: this will only set the environment variable IFS for the read statement only. So it...
Is calculating an MD5 hash less CPU intensive than SHA family functions?
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Yes, MD5 is somewhat less CPU-intensive. On my Intel x86 (Core2 Quad Q6600, 2.4 GHz, using one core), I get this in 32-bit mode:
MD5 411
SHA-1 218
SHA-256 118
SHA-512 46
and this in 64-bit mode:
MD5 407
SHA-1 312
SHA-256 148
SHA-512 189
Figures are in megabytes ...
C# List of objects, how do I get the sum of a property
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edited May 18 '17 at 10:29
Coops
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answered De...
Add missing dates to pandas dataframe
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270
You could use Series.reindex:
import pandas as pd
idx = pd.date_range('09-01-2013', '09-30-201...
List comprehension vs map
... map when using exactly the same function:
$ python -mtimeit -s'xs=range(10)' 'map(hex, xs)'
100000 loops, best of 3: 4.86 usec per loop
$ python -mtimeit -s'xs=range(10)' '[hex(x) for x in xs]'
100000 loops, best of 3: 5.58 usec per loop
An example of how performance comparison gets completely r...
How to use arguments from previous command?
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By the way, you could have put the echo on the line by selecting argument 0:
Press Alt-0 Alt-Ctrl-y
Edit:
To answer the question you added to your original:
You can press Alt-0 then repeatedly press Alt-. to step through the previous commands (arg 0). Similarly Alt-- then repeating Alt-. would ...
Performant Entity Serialization: BSON vs MessagePack (vs JSON)
...:2} is stored in a file and you want to update the value of "a" from 1 to 2000.
With MessagePack, 1 uses only 1 byte but 2000 uses 3 bytes. So "b" must be moved backward by 2 bytes, while "b" is not modified.
With BSON, both 1 and 2000 use 5 bytes. Because of this verbosity, you don't have to move...
How to replace all strings to numbers contained in each string in Notepad++?
... say that you want to match each of the following lines
value="4"
value="403"
value="200"
value="201"
value="116"
value="15"
using the .*"\d+" pattern and want to keep only the number. You can then use a capture group in your matching pattern, using parentheses ( and ), like that: .*"(\d+)". So n...
SVG drop shadow using css3
...ow.
Relevant bits from the example:
<filter id="dropshadow" height="130%">
<feGaussianBlur in="SourceAlpha" stdDeviation="3"/> <!-- stdDeviation is how much to blur -->
<feOffset dx="2" dy="2" result="offsetblur"/> <!-- how much to offset -->
<feComponentTran...
Convert a character digit to the corresponding integer in C
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As per other replies, this is fine:
char c = '5';
int x = c - '0';
Also, for error checking, you may wish to check isdigit(c) is true first. Note that you cannot completely portably do the same for letters, for example:
char c = 'b';
int x = c - 'a'; // x is now not necessarily 1
Th...