Constants
>>
<<
Usr
Pri
JfC
LJ
Phr
Dic
Voc
!:
Help
Dictionary
Constants
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.
For example,
2.3 denotes two and three-tenths and
_2.3
denotes its negation; but
_2j3 denotes a complex number with
real part
_2 and imaginary part
3 ,
not
the negation of the complex number
2j3 .
Furthermore, symbols at the same level of the hierarchy cannot be
used together:
1p2x3 is an ill-formed number.
The following lists illustrate the main points:
2.3e2 2.3e_2 2j3
230 0.023 2j3
2p1 1p_1
6.28319 0.31831
1x2 2x1 1x_1
7.38906 5.43656 0.367879
2e2j_2e2 2e2j2p1 2ad45 2ar0.785398
200j_200 628.319j6.28319 1.41421j1.41421 1.41421j1.41421
16b1f 10b23 _10b23 1e2b23 2b111.111
31 23 _17 203 7.875
Negative integers following
p and
x indicate the use
of reciprocals. For example,
2p_2 is two divided
by π squared,
and
2x_2 is two divided by the square of Euler's number.
>>
<<
Usr
Pri
JfC
LJ
Phr
Dic
Voc
!:
Help
Dictionary