HP 49g+, Руководство пользователя

Страница: 92 / 862

Page 2-37
variable, but one created by a previous exercise
CASINFO a graph that provides CAS information
MODULO Modulo for modular arithmetic (default = 13)
REALASSUME List of variable names assumed as real values
PERIOD Period for trigonometric functions (default = 2
π
)
VX Name of default independent variable (default = X)
EPS Value of small increment (epsilon), (default = 10
-10
)
These variables are used for the operation of the CAS.
Typing directory and variable names
To name subdirectories, and sometimes, variables, you will have to type
strings of letters at once, which may or may not be combined with numbers.
Rather than pressing the
~
,
~„
, or
~‚
key combinations to
type each letter, you can hold down the
~
key and enter the various letter.
You can also lock the alphabetic keyboard temporarily and enter a full name
before unlocking it again. The following combinations of keystrokes will lock
the alphabetic keyboard:
~~
locks the alphabetic keyboard in upper case. When locked in this
fashion, pressing the
„
before a letter key produces a lower case letter,
while pressing the
‚
key before a letter key produces a special character.
If the alphabetic keyboard is already locked in upper case, to lock it in lower
case, type,
„~
~~„~
locks the alphabetic keyboard in lower case. When locked
in this fashion, pressing the
„
before a letter key produces an upper case
letter. To unlock lower case, press
„~
To unlock the upper-case locked keyboard, press
~
Let’s try some exercises typing directory/variable names in the stack.
Assuming that the calculator is in the Algebraic mode of operation (although
the instructions work as well in RPN mode), try the following keystroke
sequences. With these commands we will be typing the words ‘MATH’,
‘Math’, and ‘MatH’