I found it very hard to write a regex to match j numbers. A simple
regex to match positive decimal integer is relatively easy,
d\+
but from page constants in J dictionary,
The form of a numeric constant defined and illustrated in Part I is elaborated
by the use of further letters, as in 2r3 for
two-thirds, 2p1 for two π, and 2e3p1 for 2000 π. The complete scheme of numeric
constants obeys the following hierarchy:
. The decimal point is obeyed first
_ The negative sign is obeyed next
e Exponential (scientific) notation
ad ar j Complex (magnitude and angle) in degrees or radians; Complex number
p x Numbers based on pi (o.1) and on Euler’s number (the exponential ^1)
b Base value (using a to z for 10 to 35)
Moreover, digits with a trailing x denote an extended precision integer, and
digits followed by an r followed by further
digits denote a rational number. See Section II G.
Does anyone know how to write the regex for it?
Thanks,
--
regards,
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唐詩137 劉長卿 新年作
鄉心新歲切 天畔獨潸然 老至居人下 春歸在客先
嶺猿同旦暮 江柳共風煙 已似長沙傅 從今又幾年
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