


Display Control


The HP41C provides many display capabilities for both numbers and ALPHA
characters. You can control the format of how all numbers are seen in the
display. But regardless of the display options in effect, the HP41C
always represents each number internally as a 10digit mantissa and a
2digit exponent of 10. Thus when the calculator is set to display only
four digits past the decimal point, the fixed constant pi, which is
always represented internally as 3.141592654 × 10^{00}, will
appear in the display as 3.1416.


For example, when you compute 2π, you might see the answer to
only four decimal places:




However, inside the calculator all numbers have 10digit mantissa and
2digit exponents of 10. So the calculator actually calculates
using full 10digit numbers.



yields an answer that is actually carried to full 10 digits internally:



6.283185308
× 10^{00}





You see only these digits...





...but these digits are also present internally.



Display Format Control


There are three functions,
FIX ,
SCI , and
ENG , that allow you to control the manner in which
numbers appear in the HP41C display.


FIX displays numbers in fixed decimal point format,
while SCI permits you to view numbers in scientific
notation format. ENG displays numbers in engineering
notation, with exponents of 10 shown in multiples of three (e.g., 10^{3},
10^{–6}, 10^{12}). By pressing a digit key (0 through 9)
after any of these display control functions, you specify the number of decimal
digits displayed. The HP41C will actually prompt you with an _ (underscore)
for the number (0 through 9) when you press the display format function.


No matter which format or how many digits you choose, the display control
alters only the
