43  Technical How-Tos

43.1 Missing Unicode characters

Markdown manuscript are in unicode, which allow us to enter many languages directly and a range of special symbols.

LaTeX issues a warning if a character is missing from your chosen font, for instance:

Missing character: There is no ὀ (U+1F40) (U+1F40) in font STIXTwoText:mode=node;script

In LaTeX/PDF output there are three solutions for this:

1. generate missing characters by combining other characters of the same font (typically a diacritic plus a character)
2. generate missing characters by using a math symbol command (typical for symbols)
3. use a different font for specific Unicode ranges

Methods 1-2 rely on the newunicodechar package. Method 3 on fontspec.

It’s good to have a character table for your font. See for instance STIX font docs: the character table indicates which characters can be built from others.

43.1.1 Unicode from math

You could use use LaTeX’s (inputenc’s) DeclareUnicodeChar command, if you know the character’s UTF-8 number:

\DeclareUnicodeCharacter{2234}{\ensuremath{\therefore}}
\DeclareUnicodeCharacter{2713}{\ensuremath{\checkmark}}

Or the newunicodechar package, which allows you to use the character itself:

\usepackage{newunicodechar}
\newunicodechar{∴}{\ensuremath{\therefore}}
\newunicodechar{✓}{\ensuremath{\checkmark}}

Either option requires a header-includes or a modification of your LaTeX template.

We use a metadata variable instead. This allows us to enter the desired character directly or as a HTML entity (which Pandoc converts to the desired char before passing it on to our LaTeX template):

unicodefrommath:
- char: '∴'
  is: \therefore
- char: ✓
  is: \checkmark

This is supported as follows in our Pandokoma template:

$if(unicodefrommath)$
\usepackage{newunicodechar}
$for(unicodefrommath)$
  $if(it.char)$
    $if(it.is)$\newunicodechar{$it.char$}{\ensuremath{$it.is$}}$endif$
  $endif$
$endfor$
$endif$

43.1.2 Provide Unicode characters

For LaTeX/PDF, use \DeclareUnicodeCharacter or newunicodechar.

We use pandokoma’s yaml declaration. Here is our declaration for the Greek extended block.

newunicodechar:
- char: ἀ
  command: α\symbol{"0313"}
- char: ἁ
  command: α\symbol{"0314}
- char: ἂ
  command: α\symbol{"0313}\symbol{"0300}
- char: ἃ
  command: α\symbol{"0314}\symbol{"0300}
- char: ἄ
  command: α\symbol{"0313}\symbol{"0301}
- char: ἅ
  command: α\symbol{"0314}\symbol{"0301}
- char: ἆ
  command: α\symbol{"0313}\symbol{"00342}
- char: ἇ
  command: α\symbol{"0314}\symbol{"00342}
- char: Ἀ
  command: Α\symbol{"0313}
- char: Ἁ
  command: Α\symbol{"0314}
- char: Ἂ
  command: Α\symbol{"0313}\symbol{"0300}
- char: Ἃ
  command: Α\symbol{"0314}\symbol{"0300}
- char: Ἄ
  command: Α\symbol{"0313}\symbol{"0301}
- char: Ἅ
  command: Α\symbol{"0314}\symbol{"0301}
- char: Ἆ
  command: Α\symbol{"0313}\symbol{"0342}
- char: Ἇ
  command: Α\symbol{"0314}\symbol{"0342}
- char: ἐ
  command: ε\symbol{"0313}
- char: ἑ
  command: ε\symbol{"0314}
- char: ἒ
  command: ε\symbol{"0313}\symbol{"0300}
- char: ἓ
  command: ε\symbol{"0314}\symbol{"0300}
- char: ἔ
  command: ε\symbol{"0313}\symbol{"0301}
- char: ἕ
  command: ε\symbol{"0314}\symbol{"0301}
- char: Ἐ
  command: Ε\symbol{"0313}
- char: Ἑ
  command: Ε\symbol{"0314}
- char: Ἒ
  command: Ε\symbol{"0313}\symbol{"0300}
- char: Ἓ
  command: Ε\symbol{"0314}\symbol{"0300}
- char: Ἔ
  command: Ε\symbol{"0313}\symbol{"0301}
- char: Ἕ
  command: Ε\symbol{"0314}\symbol{"0301}
- char: Ἆ
  command: Α\symbol{"0313}\symbol{"0342}
- char: Ἇ
  command: Α\symbol{"0314}\symbol{"0342}
- char: ἠ
  command: η\symbol{"0313}
- char: ἡ
  command: η\symbol{"0314}
- char: ἢ
  command: η\symbol{"0313}\symbol{"0300}
- char: ἣ
  command: η\symbol{"0314}\symbol{"0300}
- char: ἤ
  command: η\symbol{"0313}\symbol{"0301}
- char: ἥ
  command: η\symbol{"0314}\symbol{"0301}
- char: ἦ
  command: η\symbol{"0313}\symbol{"00342}
- char: ἧ
  command: η\symbol{"0314}\symbol{"00342}
- char: Ἠ
  command: Η\symbol{"0313}
- char: Ἡ
  command: Η\symbol{"0314}
- char: Ἢ
  command: Η\symbol{"0313}\symbol{"0300}
- char: Ἣ
  command: Η\symbol{"0314}\symbol{"0300}
- char: Ἤ
  command: Η\symbol{"0313}\symbol{"0301}
- char: Ἥ
  command: Η\symbol{"0314}\symbol{"0301}
- char: Ἦ
  command: Η\symbol{"0313}\symbol{"0342}
- char: Ἧ
  command: Η\symbol{"0314}\symbol{"0342}
- char: ἰ
  command: ι\symbol{"0313"}
- char: ἱ
  command: ι\symbol{"0314}
- char: ἲ
  command: ι\symbol{"0313}\symbol{"0300}
- char: ἳ
  command: ι\symbol{"0314}\symbol{"0300}
- char: ἴ
  command: ι\symbol{"0313}\symbol{"0301}
- char: ἵ
  command: ι\symbol{"0314}\symbol{"0301}
- char: ἶ
  command: ι\symbol{"0313}\symbol{"00342}
- char: ἷ
  command: ι\symbol{"0314}\symbol{"00342}
- char: Ἰ
  command: Ι\symbol{"0313}
- char: Ἱ
  command: Ι\symbol{"0314}
- char: Ἲ
  command: Ι\symbol{"0313}\symbol{"0300}
- char: Ἳ
  command: Ι\symbol{"0314}\symbol{"0300}
- char: Ἴ
  command: Ι\symbol{"0313}\symbol{"0301}
- char: Ἵ
  command: Ι\symbol{"0314}\symbol{"0301}
- char: Ἶ
  command: Ι\symbol{"0313}\symbol{"0342}
- char: Ἷ
  command: Ι\symbol{"0314}\symbol{"0342}
- char: ὀ
  command: ο\symbol{"0313}
- char: ὁ
  command: ο\symbol{"0314}
- char: ὂ
  command: ο\symbol{"0313}\symbol{"0300}
- char: ὃ
  command: ο\symbol{"0314}\symbol{"0300}
- char: ὄ
  command: ο\symbol{"0313}\symbol{"0301}
- char: ὅ
  command: ο\symbol{"0314}\symbol{"0301}
- char: Ὀ
  command: Ο\symbol{"0313}
- char: Ὁ
  command: Ο\symbol{"0314}
- char: Ὂ
  command: Ο\symbol{"0313}\symbol{"0300}
- char: Ὃ
  command: Ο\symbol{"0314}\symbol{"0300}
- char: Ὄ
  command: Ο\symbol{"0313}\symbol{"0301}
- char: Ὅ
  command: Ο\symbol{"0314}\symbol{"0301}
- char: ὐ
  command: υ\symbol{"0313"}
- char: ὑ
  command: υ\symbol{"0314}
- char: ὒ
  command: υ\symbol{"0313}\symbol{"0300}
- char: ὓ
  command: υ\symbol{"0314}\symbol{"0300}
- char: ὔ
  command: υ\symbol{"0313}\symbol{"0301}
- char: ὕ
  command: υ\symbol{"0314}\symbol{"0301}
- char: ὖ
  command: υ\symbol{"0313}\symbol{"00342}
- char: ὗ
  command: υ\symbol{"0314}\symbol{"00342}
- char: Ὑ
  command: Υ\symbol{"0314}
- char: Ὓ
  command: Υ\symbol{"0314}\symbol{"0300}
- char: Ὕ
  command: Υ\symbol{"0314}\symbol{"0301}
- char: Ὗ
  command: Υ\symbol{"0314}\symbol{"0342}
- char: ὠ
  command: ω\symbol{"0313"}
- char: ὡ
  command: ω\symbol{"0314}
- char: ὢ
  command: ω\symbol{"0313}\symbol{"0300}
- char: ὣ
  command: ω\symbol{"0314}\symbol{"0300}
- char: ὤ
  command: ω\symbol{"0313}\symbol{"0301}
- char: ὥ
  command: ω\symbol{"0314}\symbol{"0301}
- char: ὦ
  command: ω\symbol{"0313}\symbol{"00342}
- char: ὧ
  command: ω\symbol{"0314}\symbol{"00342}
- char: Ὠ
  command: Ω\symbol{"0313}
- char: Ὡ
  command: Ω\symbol{"0314}
- char: Ὢ
  command: Ω\symbol{"0313}\symbol{"0300}
- char: Ὣ
  command: Ω\symbol{"0314}\symbol{"0300}
- char: Ὤ
  command: Ω\symbol{"0313}\symbol{"0301}
- char: Ὥ
  command: Ω\symbol{"0314}\symbol{"0301}
- char: Ὦ
  command: Ω\symbol{"0313}\symbol{"0342}
- char: Ὧ
  command: Ω\symbol{"0314}\symbol{"0342}
- char: ὰ
  command: α\symbol{"0300}
- char: ά
  command: α\symbol{"0301}
- char: ὲ
  command: ε\symbol{"0300}
- char: έ
  command: ε\symbol{"0301}
- char: ὴ
  command: η\symbol{"0300}
- char: ή
  command: η\symbol{"0301}
- char: ὶ
  command: ι\symbol{"0300}
- char: ί
  command: ι\symbol{"0301}
- char: ὸ
  command: ο\symbol{"0300}
- char: ό
  command: ο\symbol{"0301}
- char: ὺ
  command: υ\symbol{"0300}
- char: ύ
  command: υ\symbol{"0301}
- char: ὼ
  command: ω\symbol{"0300}
- char: ώ
  command: ω\symbol{"0301}
- char: ᾀ
  command: α\symbol{"0313}\symbol{"0345}
- char: ᾁ
  command: α\symbol{"0314}\symbol{"0345}
- char: ᾂ
  command: α\symbol{"0313}\symbol{"0300}\symbol{"0345}
- char: ᾃ
  command: α\symbol{"0314}\symbol{"0300}\symbol{"0345}
- char: ᾄ
  command: α\symbol{"0313}\symbol{"0301}\symbol{"0345}
- char: ᾅ
  command: α\symbol{"0314}\symbol{"0301}\symbol{"0345}
- char: ᾆ
  command: α\symbol{"0313}\symbol{"0342}\symbol{"0345}
- char: ᾇ
  command: α\symbol{"0314}\symbol{"0342}\symbol{"0345}
- char: ᾈ
  command: Α\symbol{"0313}\symbol{"0345}
- char: ᾉ
  command: Α\symbol{"0314}\symbol{"0345}
- char: ᾊ
  command: Α\symbol{"0313}\symbol{"0300}\symbol{"0345}
- char: ᾋ
  command: Α\symbol{"0314}\symbol{"0300}\symbol{"0345}
- char: ᾌ
  command: Α\symbol{"0313}\symbol{"0301}\symbol{"0345}
- char: ᾍ
  command: Α\symbol{"0314}\symbol{"0301}\symbol{"0345}
- char: ᾎ
  command: Α\symbol{"0313}\symbol{"0342}\symbol{"0345}
- char: ᾏ
  command: Α\symbol{"0314}\symbol{"0342}\symbol{"0345}
- char: ᾐ
  command: η\symbol{"0313}\symbol{"0345}
- char: ᾑ
  command: η\symbol{"0314}\symbol{"0345}
- char: ᾒ
  command: η\symbol{"0313}\symbol{"0300}\symbol{"0345}
- char: ᾓ
  command: η\symbol{"0314}\symbol{"0300}\symbol{"0345}
- char: ᾔ
  command: η\symbol{"0313}\symbol{"0301}\symbol{"0345}
- char: ᾕ
  command: η\symbol{"0314}\symbol{"0301}\symbol{"0345}
- char: ᾖ
  command: η\symbol{"0313}\symbol{"0342}\symbol{"0345}
- char: ᾗ
  command: η\symbol{"0314}\symbol{"0342}\symbol{"0345}
- char: ᾘ
  command: Η\symbol{"0313}\symbol{"0345}
- char: ᾙ
  command: Η\symbol{"0314}\symbol{"0345}
- char: ᾚ
  command: Η\symbol{"0313}\symbol{"0300}\symbol{"0345}
- char: ᾛ
  command: Η\symbol{"0314}\symbol{"0300}\symbol{"0345}
- char: ᾜ
  command: Η\symbol{"0313}\symbol{"0301}\symbol{"0345}
- char: ᾝ
  command: Η\symbol{"0314}\symbol{"0301}\symbol{"0345}
- char: ᾞ
  command: Η\symbol{"0313}\symbol{"0342}\symbol{"0345}
- char: ᾟ
  command: Η\symbol{"0314}\symbol{"0342}\symbol{"0345}
- char: ᾠ
  command: ω\symbol{"0313}\symbol{"0345}
- char: ᾡ
  command: ω\symbol{"0314}\symbol{"0345}
- char: ᾢ
  command: ω\symbol{"0313}\symbol{"0300}\symbol{"0345}
- char: ᾣ
  command: ω\symbol{"0314}\symbol{"0300}\symbol{"0345}
- char: ᾣ
  command: ω\symbol{"0313}\symbol{"0301}\symbol{"0345}
- char: ᾥ
  command: ω\symbol{"0314}\symbol{"0301}\symbol{"0345}
- char: ᾦ
  command: ω\symbol{"0313}\symbol{"0342}\symbol{"0345}
- char: ᾧ
  command: ω\symbol{"0314}\symbol{"0342}\symbol{"0345}
- char: ᾨ
  command: Ω\symbol{"0313}\symbol{"0345}
- char: ᾩ
  command: Ω\symbol{"0314}\symbol{"0345}
- char: ᾪ
  command: Ω\symbol{"0313}\symbol{"0300}\symbol{"0345}
- char: ᾫ
  command: Ω\symbol{"0314}\symbol{"0300}\symbol{"0345}
- char: ᾬ
  command: Ω\symbol{"0313}\symbol{"0301}\symbol{"0345}
- char: ᾭ
  command: Ω\symbol{"0314}\symbol{"0301}\symbol{"0345}
- char: ᾮ
  command: Ω\symbol{"0313}\symbol{"0342}\symbol{"0345}
- char: ᾯ
  command: Ω\symbol{"0314}\symbol{"0342}\symbol{"0345}
- char: ᾰ
  commmand: α\symbol{"0306}
- char: ᾱ
  commmand: α\symbol{"0304}
- char: ᾲ
  command: α\symbol{"0300}\symbol{"0345}
- char: ᾳ
  command: α\symbol{"0345}
- char: ᾴ
  command: α\symbol{"0301}\symbol{"0345}
- char: ᾶ
  command: α\symbol{"0342}
- char: ᾷ
  command: α\symbol{"0342}\symbol{"0345}
- char: Ᾰ
  command: Α\symbol{"0306}
- char: Ᾱ
  command: Α\symbol{"0304}
- char: Ὰ
  command: Α\symbol{"0300}
- char: Ά
  command: Α\symbol{"0301}
- char: ᾼ
  command: Α\symbol{"0345}
- char: ι
  command: ι
- char: ῂ
  command: η\symbol{"0300}\symbol{"0345}
- char: ῃ
  command: η\symbol{"0345}
- char: ῄ
  command: η\symbol{"0301}\symbol{"0345}
- char: ῆ
  command: η\symbol{"0342}
- char: ῇ
  command: η\symbol{"0342}\symbol{"0345}
- char: Ὲ
  command: Ε\symbol{"0300}
- char: Έ
  command: Ε\symbol{"0301}
- char: Ὴ
  command: Η\symbol{"0300}
- char: Ή
  command: Η\symbol{"0301}
- char: ῌ
  command: Η\symbol{"0345}
- char: ῐ
  command: ι\symbol{"0306}
- char: ῑ
  command: ι\symbol{"0304}
- char: ῒ
  command: ι\symbol{"0308}\symbol{"0300}
- char: ΐ
  command: ι\symbol{"0308}\symbol{"0301}
- char: ῖ
  command: ι\symbol{"0342}
- char: ῗ
  command: ι\symbol{"0308}\symbol{"0342}
- char: Ῐ
  command: Ι\symbol{"0306}
- char: Ῑ
  command: Ι\symbol{"0304}
- char: Ὶ
  command: Ι\symbol{"0300}
- char: Ί
  command: Ι\symbol{"0301}
- char: ῠ
  command: υ\symbol{"0306}
- char: ῡ
  command: υ\symbol{"0304}
- char: ῢ
  command: υ\symbol{"0308}\symbol{"0300}
- char: ΰ
  command: υ\symbol{"0308}\symbol{"0301}
- char: ῤ
  command: ρ\symbol{"0313}
- char: ῥ
  command: ρ\symbol{"0314}
- char: ῦ
  command: υ\symbol{"0342}
- char: ῧ
  command: υsymbol{"0308}\symbol{"0342}
- char: Ῠ
  command: Υ\symbol{"0306}
- char: Ῡ
  command: Υ\symbol{"0304}
- char: Ὺ
  command: Υ\symbol{"0300}
- char: Ύ
  command: Υ\symbol{"0301}
- char: Ῥ
  command: Ρ\symbol{"0314}
- char: ῲ
  command: ω\symbol{"0300}\symbol{"0345}
- char: ῳ
  command: ω\symbol{"0345}
- char: ῴ
  command: ω\symbol{"0301}\symbol{"0345}
- char: ῶ
  command: ω\symbol{"0342}
- char: ῷ
  command: ω\symbol{"0342}\symbol{"0345}
- char: Ὸ
  command: Ο\symbol{"0300}
- char: Ό
  command: Ο\symbol{"0301}
- char: Ὼ
  command: Ω\symbol{"0300}
- char: Ώ
  command: Ω\symbol{"0301}
- char: ῼ
  command: Ω\symbol{"0345}

43.1.3 Background on LaTeX / unicode

To print Unicode chars by number use \symbol{} or \char. For omicron (Unicode decimal 959, hexadecimal OxO3BF):

\symbol{"03BF}
\symbol{959}
\char"03BF
\char959

To combine a character with a diacritic use the character directly followed by the combining diacritic. For instance, you can create Greek small omicron with psili (Unicode U+1F40) by combining Greek small omicron (ο, U+03BF) with the combining Greek koronis (U+0343). Any of these work:

ο\symbol{"0343}
ο\char"0343
\char"03BF\char"0343
\symbol{"03BF}\char"0343
\symbol{"03BF}\symbol{"0343}
\char"03BF\symbol{"0343}

The combining Greek Koronis is usually the same as the combining comma above (U+0313), so you could use that instead.