Expression Evaluation

Environment: VC 4.0/5.0

I made this code while working on a program for analyzing mathematical expressions, and
I made some classes for making things easier.

See sample code: express.zip ; the programme was writen using
MSVC 4.0 and compiled with MSVC 5.0

This classes can be used for evaluating expressions like :

1+4*(5+9) or

1+var1+var2*(5+b5), where var1 , var2 can be: numeric values or expressions or other
numeric stuff. See the sample code.

The class hierarchy that I implemented is :

CExpression derived from CObject – represents
a mathematical expression; use ChangeExpression to assign a string
expression to the expression object

The folowing mathematical functions are known: sin, cos, exp, sqrt, log, tg, ctg, asin,
acos, atg and the default operations like +, -,  *, /, ^ – (pow()); the abs function
is implemented using: |expresion|.

CValue derived from CObject – represents a value; use
SetValue/GetValue – to set / get the value, or UpdateValue
to Update the value

CExpValue derived from CValue – represents a value
that is defined by a expresion

CNumericValue derived from CValue – represents a
simple numeric value

The best way of understanding the way that this classes are functioning is to see the
sample project.

If you have some questions or you have some improvement ideas, or you find a bug please
send me a mail to: zolyfarkas@usa.net or zoly@csoft.dnttm.ro

See sample code: express.zip

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