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Commands using bc

Terminal - Commands using bc - 36 results

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

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Beep siren

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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

? () { echo "$*" | bc -l; }

2009-06-28 20:15:30

User: fizz

Functions: bc echo

Tags: bash bc function calc bc -l

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Define a quick calculator function

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

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Simple countdown from a given date

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 :)

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo "obase=2; 27" | bc -l

2009-03-25 09:54:50

User: polar

Functions: bc echo

Tags: bc

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Base conversions with bc

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

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Quick calculator at the terminal

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.

2009-03-24 16:19:12

User: haivu

Functions: bc

-2

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A handy calculator

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"

2009-03-18 14:20:32

User: mrttlemonde

Functions: bc echo printf xargs

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Doing some floating point calculations with rounding (e.g. at the 3rd decimal)

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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

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Five Minutes To Go

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

2009-02-21 15:55:37

User: magictoken

Functions: bc cut echo sed tr

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memcache affinity: queries local memcached for stats, calculates hit/get ratio and prints it out.

queries local memcached for stats, calculates hit/get ratio and prints it out.

echo "8000000/(20*6*86400)" | bc -l

2009-02-19 17:05:20

User: skygreg

Functions: bc echo

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doing some floating point math

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echo '2^2^20' | time bc > /dev/null

2009-02-06 02:31:55

User: mkc

Functions: bc echo time

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quick integer CPU benchmark

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.

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