7 of the Best Free Linux Calculators

An anonymous reader writes "One of the basic utilities supplied with any operating system is a desktop calculator. These are often simple utilities that are perfectly adequate for basic use. They typically include trigonometric functions, logarithms, factorials, parentheses and a memory function. However, the calculators featured in this article are significantly more sophisticated with the ability to process difficult mathematical functions, to plot graphs in 2D and 3D, and much more. Occasionally, the calculator tool provided with an operating system did not engender any confidence. The classic example being the calculator shipped with Windows 3.1 which could not even reliably subtract two numbers. Rest assured, the calculators listed below are of precision quality."

Useless.

[SanityInAnarchy]

No maxima? How about kmplot?

Missing

[bcmm]

$ dc

Where's DC/BC?

[Bananatree3]

DC [computerhope.com] or BC [computerhope.com] are more than adequate, are already in 99% of the distros out there and are chock full of features!

Re:Missing

[John Hasler]

> $ dc

And bc.

I use bc and like better than any GUI

[ls671]

I use bc and I like better than any GUI based calculator. Compiled with readline functionality, it just rocks in my humble opinion:

~$ bc
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'.
scale=5
(2*80/3.333)^3
110625.18091
((2*80/3.333)^3)/21
5267.86575

man bc for details

Emacs Calc

[macshit]

Emacs Calc, i.e. "M-x calc" in Emacs is by far the best calculator I've ever seen.

Here's the blurb from the manual:

"Calc" is an advanced calculator and mathematical tool that runs as part of the GNU Emacs environment. Very roughly based on the HP-28/48 series of calculators, its many features include:

• Choice of algebraic or RPN (stack-based) entry of calculations.
• Arbitrary precision integers and floating-point numbers.
• Arithmetic on rational numbers, complex numbers (rectangular and polar), error forms with standard deviations, open and closed intervals, vectors and matrices, dates and times, infinities, sets, quantities with units, and algebraic formulas.
• Mathematical operations such as logarithms and trigonometric functions.
• Programmer's features (bitwise operations, non-decimal numbers).
• Financial functions such as future value and internal rate of return.
• Number theoretical features such as prime factorization and arithmetic modulo M for any M.
• Algebraic manipulation features, including symbolic calculus.
• Moving data to and from regular editing buffers.
• Embedded mode for manipulating Calc formulas and data directly inside any editing buffer.
• Graphics using GNUPLOT, a versatile (and free) plotting program.
• Easy programming using keyboard macros, algebraic formulas, algebraic rewrite rules, or extended Emacs Lisp.

That list gives you a bit of an idea, but doesn't really capture how just darn cool Calc is; it just seems to do everything.... (The things I particularly value are the vector/matrix operations and the symbolic manipulation operators.)

It's (default) model is HP-style RPN, except of course with a much larger visible stack, and multi-level undo.

[You have to be careful tho because recent releases of Emacs come with two calculators -- a "simple" one, which you get with "M-x calculator", and the super incredible one you get with "M-x calc"... (yes it's kind of silly, but as usual with Emacs, there are historical reasons...]

SpeedCrunch

[Cow Jones]

I've really come to like the SpeedCrunch calculator, which is available as a Debian package, and (according to their website [speedcrunch.org]) also runs on Windows and Mac. It's probably not inteded for scientific calculations, and it can't display graphs, but it has a very simple interface ideal for quick calculations. The tooltip with the current result of unfinished expressions is a nice touch, as is the history of past calculations (session).

CJ

Re:Christ

[Ethanol-fueled]

You kinda make a good point. In my opinion, the difference between a calculator and a program is a GUI interface with buttons for numbers and functions. Almost everything mentioned in the discussion(but not the article) are command-line calculators and computer algebra systems.

Gnome's calculator is excellent for basic stuff. Compared to Windows, Linux is still severely lacking with the usability of Computer Algebra Systems - many of which are still commmand-line( in before 'Get off my lawn'), though some have very crappy GUI wrappers which open plots in new windows. That's one of my biggest pet peeves as a student and recent Linux convert. Needing 2 or three open windows(terminal, gui, plots) is too cluttered for those of us who are spoiled with things like Maple*. On the other end of the usability spectrum, there's the labyrinthine Sage, which requires running in Mozilla if you want a GUI! That caused usability problems with NoScript even before I started to use the damn thing, and now it won't even start again without tinkering. I might even make room for a Windows partition for Maple or Matlab, or run them in VMs.

* Yes, I know they make 'em for *NIX. They just might be the first Linux programs I'll actually buy.

Re:Emacs Calc

[kinthalas]

<'log(500!)>

Computation got stuck or ran too long.  Type `M' to increase the limit

<M>

max-lisp-eval-depth is now 2000

<'log(500!)>

2611.33045846

Re:Useless.

[xororand]

One of the mentioned calculators has a pretty usable CLI though: "Qalculate!" - a great calculator for dealing with units, especially currencies.

Example:

> sphere(2 furlong) * (1.293 g/m^3) to kilogram
approx. 352739.273 kg

Python+Numpy+Scipy+Matplotlib

[acheron12]

What more could you need? (Acceptable answer: Sage? [sagemath.org])

Re:Useless.

[raddan]

I am a huge fan of Landon Curt Noll's calc [isthe.com] program (known as "apcalc" in Debian/Ubuntu), and it's usually one of the very first things I install on my machine. It's CLI-only, and having it available to my via SSH means that I have a great calculator available to me anytime via my mobile phone. I don't care for RPN; calc lets me write an expression just like how I would on paper, so it is very intuitive. It has a large scientific library, too.

When I need to graph, I use gnuplot.

Re:Python+Numpy+Scipy+Matplotlib

[Anonymous Coward]

Sympy [google.com], for symbolic mathematics.

Re:RPN Better than algebraic?

[jdb2]

Could someone give an example of a problem where RPN uses fewer strokes than an algebraic order calculator (including what strokes are needed on the RPN)?

One big example is continued fractions. For example : 2 INV 2 + INV 2 + INV 2 + INV 2 +...... approximates the square root of 2.

The algebraic method would involve this unweidly and ugly expression : 1 + 1/(2+1/(2+1/(2+1/(2+1/(......)))))

jdb2

Re:RPN Better than algebraic?

[adonoman]

Any time where the order of operations that you want doesn't coincide with the "natural" algebraic order:

Algebraic: (2 + 4) * (5 + 6)
11 keystrokes

RPN: 2 4 + 5 6 + *
7 keystrokes

Re:hp48

[cruff]

Here is the X48 emulator home page [berlios.de]. I fire this up when I don't have my real 48SX with me.

Re:Christ

[Blakey Rat]

Since System 7 didn't have a TCP/IP stack, you picked something of a bad example. :) MacTCP wasn't standard equipment until much later, either 7.5 or 7.6.

I think you have rose-colored glasses on, frankly. Every OS sucked back then, to pretty much the same degree.

Re:Christ

[TheRaven64]

I was alive when Windows 3 came out and I remember the calculator well, because it didn't fit in with the rest of the environment. Unlike every other app, which had been rewritten to use the new beveled buttons, the calculator used the flat ones from Windows 2 that just flashed black when you clicked on them, rather than having a push effect. Oddly enough, it was not the same calculator that shipped with Windows 2, so someone had tweaked the UI but not thought to upgrade it to the newer controls.

Windows 3.1 and NT 3.x came with the same calculator and it wasn't until Windows 95 that MS updated the UI. The OS X calculator was pretty useless until they added the programmer mode around 10.4 or 10.5. In this mode it will display any number in binary under the main display and let you toggle individual bits by clicking on them. This is amazingly useful when debugging. It also supports RPN.

Re:hp48

[texwtf]

I am taking a circuits class with 20 other students, all of whom are using ti-89s.

doing AC steady state circuit analysis is loads faster with the hp.

for example, find the parallel equivalent for a 20, 30, and 40 ohm resistor:

HP:
20 inv 30 inv 40 inv ++ inv

ti:
1/(1/20+1/30+1/40))

11 keypresses vs. 19

When you get to complex numbers (inductors and capacitors) it's not even close. I finish calculations in well less than half the time it takes the TI users. And not because I'm some sort of superwhiz with the calculator- it just works better.

The TI is a good calculator, but you can't really appreciate the speed of RPN until you've taken the time to get practiced with it.

The HP also has an algebraic mode, fwiw, if you want the "how it looks on paper" effect. It can be helpful if you are working with a complex equation and want to make sure you have done it correctly.

So.. RPN isn't god's gift to calculation for everything, but it can be very handy in many situations.

Re:RPN is stack-based

[Luyseyal]

You're missing the point. You have to enter a space, carriage return, or some other differentiator for the calculator to know that you mean 2 then 4 not 24. This is not necessary in algebraic notation because it can all be run together. That is why s/he counted the ENTER press.

-l