HP (Hewlett-Packard) 12C Calculator User Manual


 
20 Section 1: Getting Started
File name: hp 12c pt_user's guide_English_HDPMF123E27 Page: 20 of 275
Printed Date: 2005/8/1 Dimension: 14.8 cm x 21 cm
Undo Operation
Every time you press
O
,
,
f
CLEAR
H
,
f
CLEAR
²
or
f
CLEAR
G
key to clear data, the
status indicator appears in the display.
This means you can press
to undo the last operation (i.e., to recover the
data.)
Note: the Undo function is only available immediately after data has been
cleared. When the Undo indicator is turned off no operation can be undone.
The RPN and ALG Keys
The calculator can be set to perform arithmetic operations in either RPN (Reverse
Polish Notation) or ALG (Algebraic) mode.
In Reverse Polish Notation (RPN) mode, the intermediate results of calculations are
stored automatically, hence you do not have to use parentheses.
In algebraic (ALG) mode, you perform addition, subtraction, multiplication, and
division in the traditional way, using parentheses if needed.
To select RPN mode:
Press
f]
to set the calculator to RPN mode. When
the calculator is in RPN mode, the
RPN
status indicator is lit.
To select ALG mode:
Press
f[
to set the calculator to ALG mode. When
the calculator is in ALG mode, the
ALG
status indicator is lit.
Example
Suppose you want to calculate 1 + 2 = 3.
In RPN mode, you enter the first number, press the
\
key, enter the second
number, and finally press the arithmetic operator key:
+
.
In ALG mode, you enter the first number, press
+
, enter the second number, and
finally press the equals key:
}
. Don’t forget to press
OO
before doing the
calculation.
RPN mode ALG mode
1 \ 2 + 1 + 2 }
You can choose either ALG (Algebraic) or RPN (Reverse Polish
Notation) mode for your calculations. Throughout the manual, most
examples are shown in both modes. The Keystrokes column will
indicate RPN mode or ALG mode where the keystrokes differ. When
the keystrokes are the same, the column is simply titled
“Keystrokes”.