Supports free format entry of expressions exactly as one would write on paper. The expressions are entered using graffiti or the keyboard. The calculator computes the values of all the expressions in sequence and prints out the value of the last expression.
Allows the user to define and use any number of variables.
Draws graphs of one or more functions.
Allows the user to define functions using a simple syntax.
User defined functions can be recursive.
Allows the user to write scripts using "if .... else if... else..." and "while ...." constructs.
Supports a "print" construct to print out particular expressions.
Provides the following built-in functions: sin, cos, tan, ln, exp cot, sec, csc, int, abs.
The calculator supports the concept of notebooks. A notebook is similar to a memo in the memo pad application. A user enters expressions in a notebook, computes the values, makes changes if necessary, recomputes as needed, and saves the notebook upon exiting. A notebook can be reopened at a later time to view or recompute the expressions in it.

What can I use BC_CALC for?

BC_CALC can be used to compute simple expressions like: (34+56)/3
It can be used to compute more complex expressions like:
x=34.5;
y=6.7;
x^y+ x*3.45 + ln(x);.
It can be used to compute the monthly payment on a loan using the built-in notebook, "Interest".
To compute the monthly payment on a car loan of $23,500 at an APR of 7.65% with a duration of 72 months; open the notebook "Interest", and type in the expression mn(23500, 7.65, 72); It will generate the answer 415.18.
Alternately, if the user so chooses, she may write her own monthly payment calculator using the simple scripting language.
It can be used to compute restaurant tips using the built-in notebook, "tip".
It can be used to draw graphs of one or more functions.