Proposal for a British Technical Keyboard

Martin Vlietstra proposes a new British technical keyboard that includes non-breaking spaces and some common characters used for metric symbols. In his proposal, he considered various categories of user and using the restriction of inline Unicode characters, has proposed a keyboard that will not only handle all the characters needed by SI, but will also handle many of the characters needed for chemical formulae, and includes Greek characters such as ‘π’, ‘θ’ and other commonly used symbols from mathematics and physics including ‘×’, ‘÷’ and ‘±’.  He uses the standard British keyboard as the basis for his proposal and explains how a lot of new characters can be supported using key combinations with the Alt Gr key. It covers a lot more than the extra characters for the correct display of metric symbols.

Recent articles in Metric Views have highlighted the shortcomings of the UK Windows computer keyboard, particularly the absence of a non-breaking space and the symbols [°, ², ³, μ, Ω]. I have given some thought to the practicalities of overcoming this within the UK. I don’t think that we, as a group, can accomplish much when our objective is purely the correct display of SI values. We need the assistance of other groups and, in return, they would want something out of it for themselves.

When looking to see what other disciplines could benefit by using a keyboard that supports the extensions needed for SI, I found three different categories of user:

1. The first category is the user who uses diacritics – although a few letters such as ü are occasionally used in English, diacritics are widely used in the Celtic languages. Some applications, such as WORD for Windows has an application-unique facility to enter such characters. If one wishes to enter ü in WORD, one presses “:” while pressing Ctrl, followed by “u”. Other diacritics can be entered in a similar manner. This does not work for EXCEL – I have not tried it on other Microsoft products.

2. The second category is the user who wishes to enter complex mathematical formulae. Many years ago, the computer scientist Donald Knuth invented a language called TeX which is now used by many applications to generate mathematical formulae, especially from within those applications that use HTML, either in its native mode or from behind a user interface.

3. The third category is the user who wishes to enter characters that are available as stand-alone UNICODE characters, but which do not appear on the keyboard. Such characters can be entered using various control keys, but only if one knows the appropriate UNICODE number allocated to the character. Alternatively, if a user uses such keys frequently, they might find it profitable to program such keys into the operating system and/or application.

In my view, the only viable group with whom the UKMA should ally itself is a group that represents those disciplines that fall into the third category. Broadly speaking, the disciplines that I feel could benefit from some sort of cooperation are chemists who would value a quick way to type subscript digits so that they can write H₂O rather than H2O and superscript signs so that they could write about Na⁺ ions. Physicists and engineers who would like superscript digits and signs so that they can easily write numbers like 10^-5 and would also like a selection of Greek letters so that they could write about “α-particles” rather than “alpha-particles”. Also, almost all practitioners in the STEM disciplines would benefit for having a few elementary mathematical symbols such as “×”, “÷”, ““±”, “√” and “∞” available.

First of all, we need to examine the interaction between a [UK] keyboard and various Microsoft products. The diagram below shows the keys on a typical 105-key keyboard, the type that is typically used in Microsoft Windows systems. (See below)

The keys that are of interest to us are the 48 character keys (light blue) and the six modifier keys (red). This keyboard has two Ctrl and two Shift keys, leaving four effective modifier keys: the Shift, Ctrl, Alt and Alt Gr keys.  If a character key is pressed when one or more of the modifier keys are pressed, then a different character is passed on to Windows. Everybody is familiar with using the Shift key to modify a lower case letter into an upper case letter. Other modifier keys behave in a similar fashion. Since there are four modifier keys, in theory each character key can host 16 different UNICODE characters depending on which modifier keys are pressed in conjunction with the character key. In practice however, one cannot map onto 16 UNICODE characters from a single character key.  In Windows, the Ctrl and Alt keys are widely used in conjunction with one of the character keys to generate operating system of application short-cuts while the Shift key, when used without any other modifier keys, switches between upper and lower case letters. This means that the only unallocated key combination is the Alt Gr key, either by itself or in conjunction with the Shift key.

My proposal is to use the standard British keyboard as the basis for what I wish to call the “British Technical Keyboard”.  I would then map the Greek keyboard onto the British keyboard, using the Alt Gr key when one wishes to display a Greek character rather than a Latin character. Fortunately, on the QWERTY keyboard there is a close correspondence between Latin and Greek characters – the English keyboard uses the same key for “a” as the Greek keyboard uses for “α”: this applies to most of the alphabet. The Greek keyboard uses <shift><2> and <shift><3> for ² and ³, so I propose using <Alt Gr><shift><0..9> for the superscript digits and the same, but without the Shift key for the subscript digits. Any other characters would be leveraged from other keyboards in the same way.  In following this approach, the only clash that I have found is how to display the € symbol as I would be using that key combination to display a subscript 4. The solution is only to accommodate only those Greek characters that are different from the corresponding Latin letters for example, upper case “α” is “Α” which is identical to its Latin counterpart. In this way, uppercase “ε” (<Alt Gr> + “E”) would not be allocated, so the € symbol can go there.

The use of space characters have been discussed in the past in MV, but it will not hurt to summarise the findings. UNICODE supports a number of characters that are variants of a space character. The ordinary space character with which we are all familiar (U+0040) is a variable space character – writers of applications can vary the length of white space generated by this character to enable left and right-justified text. There are however two characters that allow fixed length non-breaking spaces (i.e. the application program should not insert a new line at points denoted by these blank characters). They are the Figure space ((U+2007)) which allows the user to insert a non-breaking space which is the same width as a number and the Narrow No-Break Space which allows the user to insert a space which is a lot narrower than the Figure Space.  I suggest that one should use the NARROW NO-BREAK space as a delimiter between groups of three characters and the FIGURE SPACE as the separator between a value and its units.

Unfortunately UNICODE only supports a limited selection of superscript and subscript characters, so these have been omitted apart from the digits and the superscript “+” and “-“ signs as these two symbols are widely used in numerical work.

The full sequence of additions to the standard UK keyboard that I propose is shown below:

Name	Symbol	Key sequence	UNICODE code
Superscript 0…9	⁰… ⁹	<Alt Gr><shift> + “0” … “9”	U+2070, U+2071, U+00B2, U+ 00B3, U+2074 … U+2079
Superscript plus	⁺	<Alt Gr> + “+” (See note 1)	U+207A
Superscript minus	⁻	<Alt Gr> + ”-“	U+207B
Subscript 0…9	₀ … ₉	<Alt Gr> + “0” … “9”	U+2080 … U+2089
Alpha	α	<Alt Gr> + “a”	U+03B9
Beta	β	<Alt Gr> + “b”	U+03BA
Gamma	γ / Γ	<Alt Gr> + “g” / “G”	U+03BB / U+039B
Delta	δ / Δ	<Alt Gr> + “d” / “D”	U+03BC / U+039C
Epsilon	ε	<Alt Gr> + “e”	U+03BD
Zeta	ζ	<Alt Gr> + “z”	U+03BE
Eta	η	<Alt Gr> + “h”	U+03BF
Theta	θ / Θ	Αλτ Γρ + “u” / “U”	U+03C0 / U+03A0
Iota	ι	<Alt Gr> + “I”	U+03C1
Kappa	κ	<Alt Gr> + “k”	U+03C2
Lambda	λ / Λ	<Alt Gr> + “l” / ”L”	U+03C3 / U+03A3
Mu	μ	<Alt Gr> + “m”	U+03C4
Nu	ν	<Alt Gr> + “n”	U+03C5
Xi	ξ / Ξ	<Alt Gr> + “j” / “J”	U+03CA / U+03A6
Pi	π / Π	<Alt Gr> + “p” / ”P”	U+03C8 / U+03A8
Rho	ρ	<Alt Gr> + “r”	U+03C9
Sigma	σ / Σ	<Alt Gr> + “s” / ”S”	U+03CB / U+03AB
Tau	τ	<Alt Gr> + “t”	U+03CC
Upsilon	υ	<Alt Gr> + “y”	U+03CD
Phi	φ / Φ	<Alt Gr> + “f”/ ”F”	U+03CE / U+03AE
Chi	χ	<Alt Gr> + “x”	U+03CF
Psi	ψ / Ψ	<Alt Gr> + “c” / “C”	U+03D0 / U+03B0
Omega	ω /  Ω	<Alt Gr> + “v” / ”V”	U+03D1 / U+03B1
Euro	€	<Alt Gr> + “E” (See note 2)	U+20AC
Mid-dot	·	<Alt Gr> + “.”	U+00B7
infinity	∞	<Alt Gr> + “=”	U+221E
Plus-minus	±	<Alt Gr> + “#”	U+00B1
Multiply	×	<Alt Gr> + “>”(See note 1)	U+00D7
Divide	÷	<Alt Gr> + “<”(See note 1)	U+U+00F7
Square root	√	<Alt Gr> + “\”	U+2221A
Non-breaking fixed space		<Alt Gr> + space bar	U+2007
Narrow non-breaking space		<Alt Gr><shift> + space bar	U+202F
Notes: These characters require that <shift> be pressed on the standard UK keyboard, so will also require that <shift> be pressed on the UK Technical keyboard. The euro sign has been moved from <Alt Gr> + “4” to <Alt Gr> + “E”. This is to make way for the subscript “4”.

I did some experimenting by typing “x²” using different fonts and found that one needs to be careful in choosing a suitable font. I am unable to reproduce my actual findings here as the font used by MV is fixed. I found that the Microsoft Times New Roman font gave a very small superscript “2”, but other fonts such as Calibri behaved better. It will be a matter of experimentation for the individual user.

Finally, if one wishes to use the software associated with any alternative keyboard in Windows, without having to have the keys on their keyboard engraved, Windows has an app “On-Screen Keyboard” which is grouped with other apps in the collection “Windows Ease of Access”.  On Windows 10, it can be accessed by clicking on the Windows sign at the bottom left of the screen, selecting “Windows Ease of Access” and then selecting “On-Screen Keyboard”. I use it to remind myself of how to key in Greek letters.  

References

SI

• file:///C:/Users/vliet/Downloads/SI-Brochure-9%20(20).pdf §2.2, §2.3.4, Table 7, §5.4.3, §5.4.4

Keyboards

• https://en.wikipedia.org/wiki/Keyboard_layout
• https://commons.wikimedia.org/wiki/File:ISO_keyboard_(105)_QWERTY_UK.svg

UNICODE

• top level document: https://www.unicode.org/versions/Unicode15.0.0/
• Page 267: https://www.unicode.org/versions/Unicode15.0.0/ch06.pdf
• page 915: https://www.unicode.org/versions/Unicode15.0.0/ch23.pdf
• Annex 14: Introduction: https://www.unicode.org/reports/tr14/tr14-49.html#Properties
•  https://www.compart.com/en/unicode/block/U+2070