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Units of Measurement
The following describes the valid units of measurement for fields that accept measurements. Each unit is expressed as a two-letter abbreviation. If your measurement takes a numeric value, a decimal number can be used.
pt — points
pi — picas
in — inches
mm — millimeters
cm — centimeters
px — pixels (only recommended for HTML output, but keep in mind the size of a pixel varies by operating system, screen resolution, and web browser).
em — em space
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The size in em spaces is determined by the font in use. Each em is as large as the square of the type size, which means typically as wide as the letter m (usually the widest letter in a proportional font). For a 6 point font, an em space would be 6 points wide; for an 18 point font, it would be 18 points wide.
An em unit might be useful to simulate a small caps font by applying uppercase to the content and then specifying a font size of 0.8em.
The point is the basic unit of measurement used throughout Arbortext stylesheets. Finer levels of precision may be expressed as tenths of a point or hundredths of a point. Arbortext Editor uses 1 inch = 72.27 points for measurement.
You can specify font sizes using these additional values:
xx-small (absolute size)
x-small (absolute size)
small (absolute size)
medium (absolute size)
large (absolute size)
x-large (absolute size)
xx-large (absolute size)
larger (relative size)
smaller (relative size)
For HTML output, these values are applied according to the W3C font specification for CSS:
www.w3.org/TR/REC-CSS2/fonts.html#propdef-font-size
For PDF output and print, these values are applied as follows:
xx-small size="7pt"
x-small size="8.3pt"
small size="10pt"
medium size="12pt"
large size="14.4pt"
x-large size="17.3pt"
xx-large size="20.7pt"
larger size="1.2em"
smaller size="0.833em"
A font size can also be specified as a percent, such as 75% or 55.8%.
You can specify combinations of units, but the units must be specified. For example, to specify 5 picas and 3 points, the correct syntax is 5pi 3pt. Units other than points must always be specified explicitly (for example, 35mm-1pt, 0.45in +2pt, 1cm). The em is invalid in a combination, for example, you can't specify 5in -1em.