60
Section 5: The Display and Continuous Memory
Mantissa Display
Regardless of the display format, the HP-15C always internally holds each
number as a 10-digit mantissa and a two-digit exponent of 10. For example,
π is always represented internally as 3.141592654×10
00
, regardless of what
is in the display.
When you want to view the full 10-digit mantissa of a number in the X-
register, press
´
CLEAR
u
. To keep the mantissa in the display,
hold the
u
key down.
Keystrokes
Display
|
$
3.1416
´
CLEAR
u
(hold)
3141592654
Round-Off Error
As mentioned earlier, the HP-15C holds every value to 10 digits internally.
It also rounds the final result of every calculation to the 10th digit. Because
the calculator can provide only a finite approximation for numbers such as
or 2/3 (0.666…), a small error due to rounding can occur. This error can be
increased in lengthy calculations, but usually is insignificant. To accurately
assess this effect for a given calculation requires numerical analysis beyond
our scope and space here! Refer to the
HP-15C Advanced Functions
Handbook
for a more detailed discussion.
Special Displays
Annunciators
The HP-15C display contains eight annunciators that indicate the status of
the calculator for various operations. The meaning and use of these
annunciators is discussed on the following pages:
*
Low-power indication, page 62.
USER
User mode, pages 79 and 144.
f
and
g
Prefixes for alternate functions, pages 18-19.
RAD
and
GRAD
Trigonometric modes, page 26.
C
Complex mode, page 121.
PRGM
Program mode, page 66.
Summary of Contents for HP-15C
Page 1: ...HP 15C Owner s Handbook HP Part Number 00015 90001 Edition 2 4 Sep 2011 ...
Page 17: ...Part l HP 15C Fundamentals ...
Page 64: ......
Page 65: ...Part ll HP 15C Programming ...
Page 118: ...118 ...
