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Commands using bc from sorted by
Terminal - Commands using bc - 40 results
b(){ echo "scale=${2:-2}; $1" | bc -l; }
2009-12-23 23:44:31
User: dadi
Functions: bc echo
0

terms inclosing '()' must be enclosed by "" (soft quotes)

bash variables must be referenced: b $x/$y

ugly bracket checking (balanced, fractions...)

default precision 2

mplayer -vo dummy -ao dummy -identify * 2>&1 | grep ID_LENGTH | sed 's/.*=\([0-9]*\)/\1/' | xargs echo | sed 's/ /+/g' | bc | awk 'S=$1; {printf "%dh:%dm:%ds\n",S/(60*60),S%(60*60)/60,S%60}'
2009-09-24 10:33:19
User: Strawp
Functions: awk bc echo grep sed xargs
5

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.

bc -l <<< "x=2; p=0.5; e(l(x)*p)"
bc -l <<< s(3/5)
2009-09-02 15:41:39
User: akg240
Functions: bc
3

-l auto-selects many more digits (but you can round/truncate in your head, right) plus it loads a few math functions like sin().

tempo=33; slope=10; maxfreq=888; function sinus { echo "s($1/$slope)*$maxfreq"|bc -l|tr -d '-'; }; for((i=1;;i++)); do beep -l$tempo -f`sinus $i`; done
2009-07-10 21:24:11
User: 5z474n
Functions: bc echo tr
1

Infinitely plays beeps with sinusoidally changing sound frequency. Ideal for alarm on an event.

? () { echo "$*" | bc -l; }
2009-06-28 20:15:30
User: fizz
Functions: bc echo
57

defines a handy function for quick calculations from cli.

once defined:

? 10*2+3
watch --no-title -d -n 1 'echo `date -d "next Thursday" +%s` "-" `date +%s` | bc -l'
2009-03-29 06:53:09
User: jnash
Functions: bc watch
0

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 :)

echo "obase=2; 27" | bc -l
2009-03-25 09:54:50
User: polar
Functions: bc echo
Tags: bc
20

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.

echo "$math_expr" | bc -l
2009-03-25 09:46:01
User: polar
Functions: bc echo
Tags: bc
2

Useful for quick calculations at the command line. $math_expr is any arithmetic expression (see sample output):

4.5*16+3^2

s(3.1415926/2)

More options in the bc man page.

bc
2009-03-24 16:19:12
User: haivu
Functions: bc
-2

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.

echo '123/7' |bc -l |xargs printf "%.3f\n"
for i in $(seq 0 5) ; do echo "5 - $i" | bc -l ; sleep 60 ; done && echo "bye, bye" && shutdown -h now
2009-03-13 12:16:35
User: arctarus
Functions: bc echo seq shutdown sleep
-14

command to turn off your computer when you go home and can not wait

echo -en "stats\r\n" "quit\r\n" | nc localhost 11211 | tr -s [:cntrl:] " "| cut -f42,48 -d" " | sed "s/\([0-9]*\)\s\([0-9]*\)/ \2\/\1*100/" | bc -l
echo "8000000/(20*6*86400)" | bc -l
echo '2^2^20' | time bc > /dev/null
2009-02-06 02:31:55
User: mkc
Functions: bc echo time
1

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.