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Calculate a transcendental number (pi)

Terminal - Calculate a transcendental number (pi)
seq 1 2 99999999 | sed 's!^!4/!' | paste -sd-+ | bc -l
2011-02-09 23:36:07
User: flatcap
Functions: bc paste sed seq
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.

Show sample output | Add to favourites | Report as malicious

Alternatives

There are 4 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

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What others think

Who needs all this math crap on the command line?

Comment by bashrc 119 weeks ago

Chill out man.

It's not really about what we're working out.

It's about using exising tools in creative ways.

Comment by flatcap 119 weeks ago

nice, but somehow unprecise with lower numbers.

Comment by oernii3 118 weeks and 3 days ago

Your point of view

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