HP 50G, Руководство пользователя

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This time the CASDIR is highlighted in the screen. To see the contents of the
directory press the
@@OK@@
soft menu key or
`
, to get the following screen:
The screen shows a table describing the variables contained in the CASDIR
directory. These are variables pre-defined in the calculator memory that
establish certain parameters for CAS operation (see appendix C). The table
above contains 4 columns:
•
The first column indicate the type of variable (e.g., ‘EQ’ means an
equation-type variable, |R indicates a real-value variable, { } means a list,
nam means ‘a global name’, and the symbol represents a graphic
variable.
•
The second column represents the name of the variables, i.e., PRIMIT,
CASINFO, MODULO, REALASSUME, PERIOD, VX, and EPS .
•
Column number 3 shows another specification for the variable type, e.g.,
ALG means an algebraic expression, GROB stands for graphics object ,
INTG means an integer numeric variable, LIST means a list of data,
GNAME means a global name , and REAL means a real (or floating-point)
numeric variable.
•
The fourth and last column represents the size, in bytes, of the variable
truncated, without decimals (i.e., nibbles). Thus, for example, variable
PERIOD takes 12.5 bytes, while variable REALASSUME takes 27.5 bytes (1
byte = 8 bits, 1 bit is the smallest unit of memory in computers and
calculators).
CASDIR Variables in the stack
Pressing the
$
key closes the previous screen and returns us to normal
calculator display. By default, we get back the TOOL menu:
We can see the variables contained in the current directory, CASDIR, by
pressing the
J
key (first key in the second row from the top of the keyboard).
This produces the following screen: