What is Reddit's opinion of Qalculate!?

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Qalculate or only libqalculate with the qalc shell interface:

$ qalc > 1024byte to kilobyte

1024 * byte = 1,024 kilobytes

> 1024byte to kibibyte

1024 * byte = 1 kibibyte

> 54,43gibibyte - 1000mebibyte + 2gigabyte

(54,43 * gibibyte) - (1000 * mebibyte) + (2 * gigabyte) = approx. 59,395191 gigabytes

> 54,43gibibyte - 1000mebibyte + 2gigabyte to megabyte

(54,43 * gibibyte) - (1000 * mebibyte) + (2 * gigabyte) = approx. 59395,191 megabytes

>

(german locale...so "," as decimal separator)

This is pretty cool, but I'd like to point you towards my favorite engineering calculator, Qalculate. It's handles units, and also allows for the solving of equations. Here's the example from your readme:

multisolve([20'a' + −40 'b' +52 'c' = 45.6; 2.2e−6 'a' + 4 'b' + 9 'c' = −4; −1 'a' + 1 'b' + 2.23e3 'c' = 0], ['a', 'b', 'c']) [0.2759332, −1.0012888, 0.00057274531]

Have you tried 'Qalculate!'? There is a CLI version that you can call from bash. Here are the date/time functions: https://qalculate.github.io/manual/qalculate-definitions-functions.html#qalculate-definitions-functions-1-Date--Time

Do you plan on adding units conversion, like Qalculate has? It's a massively complicated problem, but some of the more simple unit conversions should be easy. That's the main thing that I use qalc for, but its commandline interface isn't that great.

I did until I discovered Qalculate!: https://qalculate.github.io/

Qalculate! includes a command-line interface.

Here's a short review that provides a nice overview:
Qalculate! – The Best Calculator Application in The Entire Universe
https://itsfoss.com/qalculate/

krunner is a frontend to libqalculate...anything you prefix with "=" gets send to libqualculate for evaluation. That means you can use the qalculate currency conversion directly in krunner (and not the standard one krunner does if you just type "4$")...there is just one problem, you can't use the "to" keyword in krunner for some reasons (That is something I miss so much in krunner). But =10EUR = x USD works...it assignes the USD value to "x" and gives it as result. List of currencies here

Edit: Sorry, no clue about qalculate-qt, I never used it...I either user krunner or qalc in the shell.

You can't. qalculate doesn't support storage units: https://qalculate.github.io/features.html

Try: qalc "2 MB + 3 KB"

Trivia: the qalc cmdline utility has its own share of deps (~ 7 MB). bcal is a ~40 KB binary.

~~Krunner only seems to do basic math(+, -, *, /, %) but cannot do trigonometry or anything else slightly more advance. While it is really convenient for what it does~~

To do more advanced math that four banging, you can start with a = and it will treat the rest as a calculation and will do trigonometry, solve functions, can do calculations with units. Here are some examples and Here's a full list of functions

Sorry, not sure about krunner itself. It uses qalculate for the currency conversation in the background...so in a shell you can do

$qalc -e > 100€ to $

100 * euro = 118,14 $

> 100USD to AUD

100 * dollar = approx. 125,96919 AUD

The qalc -e updates the currency data from the net at start. Sadly the "to" operator doesn't seem to work in krunner (I really, really miss that one...I haven't found a way to convert decimal to binary either in krunner yet). List of currency units here.

Also...putting "100USD", "100 USD" or "100 usd" in krunner works for me too...so the same as using "$".

Try it with qalc in the shell...has the same behavior. As far as I know libqalculate is the backend for krunners calculator...so probably not much that krunner can do about it.

Calculating software with units you say? How about units?

$ units Currency exchange rates from FloatRates (USD base) on 2021-01-17 3677 units, 109 prefixes, 114 nonlinear units

You have: 1 * 3 millilightseconds You want: miles * 558.84719 / 0.0017893979

It's actually a pretty great program but jokes aside: The Ti-Nspire Software is harder to run on Linux than Linux on a Ti-Nspire. And I don't know whether anyone actually managed the former.

What exactly do you want to do? Just a calculator? I use units, bc and Qalculate.

If you also want to connect to a Ti calculator I'd look into TilP.

I got 1.2304717×10^(-6) W

I recommend downloading https://qalculate.github.io, it's what I use for physics calculations and it makes these calculations very easy since it automatically converts units.

I just typed "3.2 MBq × 2.4 MeV to watt" and it did the job.

KAlgebra is good for plotting graphs but for calculating it lacks a lot of graphics components to help user entering complex expressions. What I mean by advanced calculation is having more features like the ability to show the whole operations expressions in text area with full history and ability to do conversion of bases and units. KCalc feels like tool created for elementary school students.

Convert date to timestand:

timestamp(Y-M-D)=

"=" is important to tell krunner it's a libqalculate expression to evaluate.

Examples: timestamp(2020-12-31)= returns 1609369200

timestamp(now)= returns unix timestamp for right now

Convert unix timestamp to date:

stamptodate(timestamp)=

Examples:

stamptodate(1609369200)= returns "2020-12-31T00:00:00"

For more functions check the qalculate docs...most of those work, exceptions I have found so far are syntax related like the conversion stuff with to as you can't manage a "=" in there so krunner doesn't recognize it as qalculate expression. `

> functionally superior to the one in 7.

The only thing I can find online is that a "currency converter mode" was added. What makes it functionally better than the one in 7, and what makes it functionally better than a freeware or open-source option like Qualculate or Microsoft Mathematics?

I had quickly Googled the range of distances for the habitable zone (to calculate the width of it; Wikipedia says it's between 0.95 AU and 2.4 AU from the sun), and the average distance from Pluto to the Sun (5,906,380,000 km). Then I doubled the latter to get a rough 'diameter' for the solar system, and plugged everything into a calculator that supports units (I used Qalculate).

Basically I put my diameter for the real solar system in km, divided by 1 yard, multiplied by one inch, and had it convert the result to kilometers to get how far one inch of the model represents in real life. Qalculate supports AUs as a unit, so for the width of the habitable zone I just plugged in 2.4AU - 0.95AU and had it convert that to kilometers.

I suck at mental math, so it's easier for me to just give results from a calculator. They're still approximate anyway, since the values I used to begin with are approximate - so I made sure to use words like 'roughly' and 'about'. It's just easier to copy/paste results from an actual calculator for me, than to spend time trying to get my brain to do arithmetic (even rough arithmetic) on its own.

Try log10(.01)=

If you use log(.01) in qalculates shell backend qalc you get this:

$ qalc > log(.01)

log(0,01; e) = approx. -4,6051702

It uses "e" as base. Can have a look here. But not everything that works in qalculate also works in krunner, I couldn't get the arbitory base with log(Value[, Base]) to work for example. But it's still often a good start for why krunner behaves like it does as well as reference for functions worth trying out in krunner...now if krunner would only allow the to keyboard as in 45 to bin...that qalc functionality I really miss dearly in krunner.

Edit: For what works..it seems krunner can't use any function of qalculate that has more than one parameter for me, circle(4)= works, cone(4, 5) doesn't. But could be a language problem and german using "," as floating point separator because I can use log10(0,01)= and get the correct answer. Seems that breaks all functions needing "," to separate parameters..at least I would guess so. I would be interested to hear if this works in an US locale.

> You can't. qalculate doesn't support storage units: https://qalculate.github.io/features.html

> Try: qalc "2 MB + 3 KB"

2 mebibytes + 3 kibibytes to kibibytes

(2 * mebibyte) + (3 * kibibyte) = 2051 kibibytes