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Commands tagged math

Commands tagged math from sorted by
Terminal - Commands tagged math - 13 results
dc -e '10 [q]sq[dd1=q1-lxx*]dsxxp'
2011-02-16 19:00:21
User: mwgamera
Tags: math factorial
0
Up
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Calculate N!

More readable version of factorial calculation using standard desktop calculator instead of bc.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $(($(seq -s* 10)))
2011-02-10 18:44:53
User: minduim
Functions: echo seq
Tags: math factorial
1
Up
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Calculate N!

Same as the seq/bc solution but without bc.

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for((r=1;r<10;r++));do v=1;echo -n "$v ";for((c=1;c<$r;c++));do v2=$(($(echo "$v*($r-$c)/$c")));echo -n "$v2 ";v=$v2;done;echo;done
2011-02-10 18:38:04
User: flatcap
Functions: echo
Tags: bash math
0
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Generate Pascal's Triangle

http://en.wikipedia.org/wiki/Pascal%27s_triangle

This one's for bartonski. Enjoy.

132 characters. I'm sure we can do better.

Note: after row 64 we overflow integer maths.

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echo $(( $(echo 1 "* "{2..10}) ))
2011-02-10 17:09:28
User: glaudiston
Functions: echo
Tags: math factorial
2
Up
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Calculate N!
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seq -s^2+ 11 |rev| cut -d'+' -f2- | rev | bc
2011-02-10 08:41:14
User: foolano
Functions: cut rev seq
Tags: seq sum math
-2
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Calculate 1**2 + 2**2 + 3**2 + ...

I can't put the last ^2 with seq, so I reverse it to delete the last +N. So for doing sum(N^2) you have to do sum((N+1)^2). Must be a better way.

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seq -s* 10 |bc
2011-02-10 08:03:19
User: foolano
Functions: seq
Tags: math factorial
8
Up
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Calculate N!
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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
0
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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.

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seq 1000 | paste -sd+- | bc
2011-02-09 20:03:49
User: foolano
Functions: paste seq
Tags: sum math algebra
2
Up
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1+2-3+4-5+6-7 Series
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seq 10 | paste -sd* | bc
2011-02-09 19:56:12
User: foolano
Functions: paste seq
Tags: math factorial
1
Up
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Calculate N!
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echo 'obase=16; C+F' | bc
2010-04-14 20:35:31
User: rkulla
Functions: echo
Tags: hex bc math asm
3
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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)

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perl -MStatistics::Descriptive -alne 'my $stat = Statistics::Descriptive::Full->new; $stat->add_data(@F[1..4]); print $stat->variance' filename
2010-04-02 21:16:12
User: alperyilmaz
Functions: perl
Tags: statistics perl math
1
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statistics in one line

In this example, file contains five columns where first column is text. Variance is calculated for columns 2 - 5 by using perl module Statistics::Descriptive. There are many more statistical functions available in the module.

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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
Up
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Leap year calculation
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expr 512 \* 7
2009-09-23 19:11:38
User: chuckr
Functions: expr
Tags: math expr
4
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Quick command line math

expr will give you a quick way to do basic math from the CLI. Make sure you escape things like * and leave a space between operators and digits.

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