SI unit support

[Former user]

Originally reported on Google Code with ID 488

Support for SI units would be useful. Some calculators have keys for them, and when
in engineering mode will automatically use them for displaying results. It would be
nice if results automatically used SI units if the input did.

Suggested units:

n - nano  (10^-12)
p - pico  (10^-9)
u - micro (10^-6)
m - milli (10^-3)
K - kilo  (10^3)
M - mega  (10^6)
G - giga  (10^9)
T - tera  (10^12)

Having these units would allow all SI based measurements to use them, with no special
support needed for say kilometres or milligrams. Most electrical and scientific units
are SI (voltage, current, power, capacitance, resistance, inductance, temperature).

For bonus points also support power of 2 units for kilobyte, megabyte, gigabyte etc.

Not sure how this could be implemented without conflicting with variable names. Perhaps
hold ctrl and press the relevant key, resulting in the letter being in italics or something.
Or just disallow those names for variables in engineering mode.

Reported by mojo.chan on 2014-03-03 16:58:03

[Former user]

Thanks for your suggestion. So far I don't see a potential conflict with variable names
as the numbers would be inserted as 1.234m or 5.67k, which are invalid tokens right
now.

> For bonus points also support power of 2 units for kilobyte, megabyte, gigabyte etc.

Not sure I understood what you meant.

Reported by helder.pereira.correia on 2014-03-03 19:31:21 - Labels added: Type-Enhancement

[Former user]

Thanks for the response. Real calculators with these keys are not that common any more,
 unfortunately. By power of two units what I mean is in a certain mode 'k' would be
interpreted as kilobytes, or 2^10. Useful for programmers.

Reported by mojo.chan on 2014-03-03 19:55:56

[Former user]

Understood the power of two part now, thanks. This should work too https://en.wikipedia.org/wiki/Binary_prefix#Specific_units_of_IEC_60027-2_A.2_and_ISO.2FIEC_80000

Reported by helder.pereira.correia on 2014-03-03 20:07:08

[Former user]

I refuse to use the silly kibi/mebi names... kilobyte is 1024 bytes, end of :-) Trying
to redefine it just confuses things. I'd suggest using kb/mb/gb suffixes.

Reported by mojo.chan on 2014-03-03 21:54:34

[Former user]

Issue 497 has been merged into this issue.

Reported by helder.pereira.correia on 2014-04-04 22:03:45

[Former user]

If support was made for kilobyte, megabyte and so one, I would also prefer seeing kB,
MB, GB, TB ... that is if it can accept dual-character tokens.

Reported by KaneEvansMcLeod on 2014-07-20 08:03:32

[Former user]

I too would prefer proper power of 2 units, i.e. kb, mb, gb etc. There is already just
"k" for multiples of 1000.

Reported by mojo.chan on 2014-07-20 09:30:24

[Former user]

I am a bit of a stickler with regards to capitalisation, but mb, Mb, mB and MB are uniquely
different. Ok, so maybe having a "b" or "B" isn't going to make a difference  with
regards to a calculator, but the leading unit needs to be strict... Just think of the
puppies. Every time SI units are used wrong, a puppy dies :( I like puppies.

Reported by KaneEvansMcLeod on 2014-07-21 00:39:23

[Former user]

As long as there isn't an 'i' in there I'm happy :)

Reported by mojo.chan on 2014-07-21 13:13:50

[Former user]

Amen to that!

Reported by KaneEvansMcLeod on 2014-07-24 08:30:11

[Former user]

Are there any plans for this feature in SpeedCrunch? Support for SI prefixes is really
the only reason left to use MiscEl instead of SpeedCrunch for some calculations for
me. 

Reported by henke.k on 2015-06-10 06:24:37

[Former user]

Reported by helder.pereira.correia on 2015-06-10 16:23:56 - Status changed: Accepted

[Helder Correia]

Similarly to my question on another issue, did you find it not useful to define these units as built-in?

[Pol Welter]

No I'd sure like to have them builtin. I wonder why after redefining nano for the n-th time I still haven't actually done it properly. xD

[Pol Welter]

Issue #153 was marked as a duplicate of this issue.

[Helder Correia]

Ah, I thought I was overlooking some important blocker. Glad it was just forgotten :) Same goes with centimeter, foot, yard, kph, mph, minute, hour, etc (etc not an unit ;)

[Pol Welter]

Issue #638 was marked as a duplicate of this issue.