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Comment by tromp | Hacker News Reader

bc -l is my standard command-line tool for arbitrary precision calculations (-l not needed here but handy for functions like sqrt(), e(), and log l() ):

    $ bc -l
    bc 1.06
    Copyright 1991-1994, 1997, 1998, 2000 Free Software 
    Foundation, Inc.
    This is free software with ABSOLUTELY NO WARRANTY.
    For details type `warranty'. 
    9999999999999999.0 - 9999999999999998.0
    1.0

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I got tired of typing bc -l years ago, I have a function so I can do it on the command line: calc 2^27 + 3^15. I wish somehow the shell would let me add parens here, instead of having to escape them with a quote.

function calc2 { if [ $# -eq 0 ]; then echo 'pass commands for math evaluation, like calc l(2^32/17) + 3'; fi; echo $* | bc -l; }

This is what I've had in my bashrc for a few years:

= () { printf "%'.f\n" $(echo $1 | bc); }; alias calc==

bc is my calculator for pretty much everything for decades now. lol

who does not use bc? people who aren't old unix people ;-) I use bc

I consider myself an old unix person, but I use dc. Possibly to make it more confusing to anyone who looks at what I'm doing.

It also gives the math result here of course.

  % dc
  9999999999999999.0 9999999999999998.0 - p
  1.0
  %

I guess old unix persons do use bc. But even older unix persons, like you and me, use dc. Oh, and I still have my trusty old HP48GX calculator that I bought nearly thirty years ago. Algebraic notation is fine for paper, bur RPN is best for calculating. I am glad I can even have an RPN calculator (PCalc) on my phone now.

rpn for for the win I guess ;-). I actually didn't get to try my first linux stuff until grad school in the 80s. I wish I had saved off all my init files from then to see what they look like now.

Back in the day (Unix Seventh Edition) bc was just a front end that compiled the expression and piped it to dc. My take it is most people didn't find rpn a win, and bc was the fix.

I used bc's compiled output ("bc -c") to learn how to make dc jump through hoops.

https://man.cat-v.org/unix_7th/1/bc

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