CHAPTER 8
750
Interactive Features
To use a number format array to create a text string containing the appropriately
formatted units for display in a user interface, apply Algorithm 8.2:
Algorithm 8.2
1.
The entry in the rectilinear measure dictionary (see Table 8.111) that references
the number format array determines the meaning of the initial measurement val-
ue. For example, the
X
entry specifies user space units, and the
T
entry specifies
degrees.
Multiply the value specified above by the
C
entry of the first number format dic-
tionary in the array, which converts the measurement to units of the largest gran-
ularity specified in the array. Apply the value of
RT
as appropriate.
If the result contains no nonzero fractional portion, concatenate the label speci-
fied by the
U
entry in the order specified by
O
, after adding spacing from
PS
and
SS
. The formatting is then complete.
If there is a nonzero fractional portion and no more elements in the array, format
the fractional portion as specified by the
RD
,
F
,
D
, and
FD
entries of the last dictio-
nary. Concatenate the label specified by the
U
entry in the order specified by
O
, af-
ter adding spacing from
PS
and
SS
. The formatting is then complete.
If there is a nonzero fractional portion and more elements in the array, proceed to
the next number format dictionary in the array. Multiply its
C
entry by the frac-
tional result from the previous step. Apply the value of
RT
as appropriate. Then
proceed to step 3.
2.
3.
4.
5.
Note:
The concatenation of elements in this process assumes left-to-right order. Doc-
uments using right-to-left languages can modify the process and the meaning of the
entries as appropriate to produce the correct results.
x
or
y
are
expressed in miles; distances are expressed in miles, feet, and inches; and area is
expressed in acres. Given a sample distance in scaled units of 1.4505 miles, the
formatted text produced by applying the number format array would be
“1 mi 2,378 ft 7 5/8 in”
.