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terms inclosing '()' must be enclosed by "" (soft quotes)
bash variables must be referenced: b $x/$y
ugly bracket checking (balanced, fractions...)
default precision 2
You're behind on your TV catch-up, but how far behind? This command tries to open mplayer against all files in the current dir. If it's a video file it will contain ID_LENGTH, which is summed and output in hours, minutes and seconds.
Someone better at awk could probably reduce this down a lot.
One pipe less.
-l auto-selects many more digits (but you can round/truncate in your head, right) plus it loads a few math functions like sin().
Infinitely plays beeps with sinusoidally changing sound frequency. Ideal for alarm on an event.
defines a handy function for quick calculations from cli.
Might be more useful if you were able to print it in Days HH:MM:SS format as:
perl -e '@p=gmtime(234234);printf("%d Days %02d:%02d:%02ds\n",@p[7,2,1,0]);'
But I'm not exactly sure how to replace the 234234 with the output of the countdown time. (Having some problems with nested quoting/command substitution). Help would be appreciated :)
Easily convert numbers to their representations in different bases. Passing
"ibase=16; obase=8; F2A"
to bc will convert F2A (3882 in decimal) from Hex to Octal, and so on.
Useful for quick calculations at the command line. $math_expr is any arithmetic expression (see sample output):
More options in the bc man page.
bc is a wonderful calculator. Just type bc at the command line and have at it. Ctrl+D (or type quit) will get you out. This usage is just scratching the surface: bc can handle a mini scripting language, complete with variable, statements, loop, conditional statements and more. Do a man page on it to find out.
command to turn off your computer when you go home and can not wait
queries local memcached for stats, calculates hit/get ratio and prints it out.
This is a quick and dirty way to generate a (non-floating-point) CPU-bound task to benchmark. Adjust "20" to higher or lower values, as needed. As a benchmark this is probably a little less bogus than bogomips, and it will run anywhere 'bc' does.