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Commands tagged bc

Terminal - Commands tagged bc - 15 results

hex() { bc <<< "obase=16; $1"; }

2011-12-09 13:57:05

User: bjomape

Functions: bc

Tags: bash hex bc numbers

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convert from decimal to hexadecimal

Use the standard calculator bc to convert decimals to hex

seq 1 2 99999999 | sed 's!^!4/!' | paste -sd-+ | bc -l

2011-02-09 23:36:07

User: flatcap

Functions: bc paste sed seq

Tags: sed seq bc paste math

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Calculate a transcendental number (pi)

Calculate pi from the infinite series 4/1 - 4/3 + 4/5 - 4/7 + ...

This expansion was formulated by Gottfried Leibniz: http://en.wikipedia.org/wiki/Leibniz_formula_for_pi

I helped rubenmoran create the sum of a sequence of numbers and he replied with a command for the sequence: 1 + 2 -3 + 4 ...

This set me thinking. Transcendental numbers!

seq provides the odd numbers 1, 3, 5

sed turns them into 4/1 4/3 4/5

paste inserts - and +

bc -l does the calculation

Note: 100 million iterations takes quite a while. 1 billion and I run out of memory.

echo "e("{1..8}");" | bc -l

2010-11-18 21:18:22

User: unefunge

Functions: bc echo

Tags: bc

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Generate trigonometric/log data easily

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

seq 8 | awk '{print "e(" $0 ")" }' | bc -l

2010-08-14 02:52:39

User: polar

Functions: awk bc seq

Tags: awk seq bc

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Generate trigonometric/log data easily

If you want a sequence that can be plotted, do:

seq 8 | awk '{print "e(" $0 ")" }' | bc -l | awk '{print NR " " $0}'

Other bc functions include s (sine), c (cosine), l (log) and j (bessel). See the man page for details.

echo "($(date +%s)-$(date +%s -d "march 1"))/86400"|bc

2010-07-22 19:44:50

User: nickwe

Functions: echo

Tags: echo bc date

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find out how many days since given date

Exactly the same number of characters, exactly the same results, but with bc

echo 'obase=16; C+F' | bc

2010-04-14 20:35:31

User: rkulla

Functions: echo

Tags: hex bc math asm

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Hex math with bc

To do hex to binary: echo 'ibase=16; obase=2; 16*16' | bc # prints: 111100100

To do 16*16 from decimal to hex: echo 'ibase=10; obase=16; 16*16' | bc # prints: 100

You get the idea... Alternatively, run bc in interactive mode (see man page)

year=2010; math=`echo "$year%4" | bc`; [ ! -z $year ] && [ $math -eq 0 ] && echo "$year is leap year!" || echo "$year isn't leap year";

2010-03-30 15:33:00

User: mvrilo

Functions: echo

Tags: echo bc math

-1

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Leap year calculation

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo $((3.0/5.0))

2009-09-03 16:35:09

User: andrew112358

Functions: echo

Tags: bc floating point

-6

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floating point operations in shell scripts

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo "5 k 3 5 / p" | dc

2009-09-03 00:21:54

User: xamaco

Functions: echo

Tags: bc floating point dc

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floating point operations in shell scripts

using bc is for sissies. dc is much better :-D

Polish notation will rule the world...

bc -l <<< s(3/5)

2009-09-02 15:41:39

User: akg240

Functions: bc

Tags: bc floating point

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floating point operations in shell scripts

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

echo "scale=4; 3 / 5" | bc

2009-08-21 21:51:46

User: foob4r

Functions: echo

Tags: bc floating point

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floating point operations in shell scripts

allows you to use floating point operations in shell scripts

echo $( du -sm /var/log/* | cut -f 1 ) | sed 's/ /+/g'

2009-07-31 21:42:53

User: flux

Functions: cut du echo sed

Tags: echo bc

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cooking a list of numbers for calculation

When you've got a list of numbers each on its row, the ECHO command puts them on a simple line, separated by space. You can then substitute the spaces with an operator. Finally, pipe it to the BC program.

? () { 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

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.