Numbers And Types - Casio Reckon User Manual

To assign a variable, use syntax X=value. In RPN this can be thought of as STO by entering a variable name
(e.g. X) then use arrow, , as STO.
Whenever a variable is bound to a value, the variable will be replaced by the value during evaluation.
Variables initially have no value and are unbound. Unbound variables are useful to represent formulae, e.g.
as input to Plot() or Solve().
It is possible to unbind a variable using purge(). The purge function is mapped to SHIFT 8 (labelled CLIP).
Unfortunately, calling Purge(X) when X is bound results in Purge(value-of-x) which is not what you want.
To avoid this, you must quote X with the single quote operator 'X. quote is bound to SHIFT COMMA.
Example:
> A=3
3
> A+1
4
> A=2A
6
Purge('A)
A
Note that expressions passed into Solve() and Plot() must involve a single unbound variable. All bound
variables are replaced by their values; Plot and Solve, determine the relevant unbound variable as the
intended term to plot against or solve for.
Variables used in vectors are expanded to their values at vector creation. The vector does not remember
the variable used when creating it.
Example:
> A=1
1
> B=2
2
C=[A,B]
[1 2]
D=[C,C+2]
[[1 2]
[3 4]]
1/D
[[-2 1]
[1.5 -0.5]]

Numbers and Types

Reckon's evaluator performs automatic value type promotion. What that means is that a parameter of one
type can be automatically converted to another type in order to continue evaluation.
When you enter a number like 3, it starts life as an integer. But if you square root it, Reckon promotes the
value to floating point in order to apply the square root operation. Before values wind up as floating point,
calculations are in exact rationals.
Example:
> 69! (shift 3 key)
171122452428141311372
468338881272839092270
544893520369393648040