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Expr.vbx v1.1
Copyright, May 1995, Minxiu Chen, All Rights Reserved
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===========
The program
===========

Expr.vbx is a vbx file, which parses the text inputed by the user to
see if it is a numerical expression.  If so,  it do infix arithmetic 
expression parsing. 

The source code is written in C. It use so called "recursive descent" 
technique and  analysis the text to be set at the property "Strinput".
The  results  will be given at properties "NumValue", "IsNumExpr" and
 "StrLength."

It supports operators:
" +,  -,  *,  /, %,  ^ " 

and functions: 
" sin,  cos, tan, ctg or ctn, asin,  acos, atg, ln, lg or log10,  
exp, abs, sqrt, sqrt3, fix, rand or rnd."

and constants:
"pi or Pi, e"

All these functions are self-explanatory, 
	sqrt3(8) --> 2,
	rand(10) --> a random value between 0 and 10
	11%4 --> 3
	15.2%4.2 --> 2.6
	230 could be written as 2.3E2
	3^3 -->27
	(123 + sin(pi/2)) * 4^5* ln(exp(56))%11->3

A demo VB code and a dll file are also included. If the user don't have
vbrun300.dll in his/her window/system directory, he/she should download
vbrun300.dll from SimTel, CICA or other sites and put in same directory
as expr.exe or search path to run the expr.exe.

Functions provided by expr.dll:

float _export   far pascal expres( char FAR *S)
int  far pascal chkexpr(char FAR *S)

The declare statement for VB:
Declare Function chkexpr Lib "expr.dll" (ByVal S As String) As Integer
Declare Function expres Lib "expr.dll" (ByVal S As String) As Double

============
Registration                                                            	                               Registration
============

The program EXPR.VBX is distributed as a shareware program. It is 
distributed in completed state, there are no nagging message. 
You have the right to test this program for 10 days. You are 
allowed to copy this package  and give it to any other person, 
as long as it is not modified in any way.

after the trial period, If you find it useful and want to keep using it,
You are obliged to register your copy. when updated, the registered user
will automatic get all newer versions. The register user may get a free
shtdll11.zip  if he/she wish.      Shtdll11.zip is a dll file for opening
and reading lotus wk1 and excel xls sheets.

This software may NOT be used for commercial purpose without registration. 
 

==========
Disclaimer
==========

The program has been tested to keep it as bug-free.  But I still 
declare that it is supplied "As is"  without warranty of any kind. 
You use it at your own risk.   I accept no responsibility for
any damage or loss, physical, financial, or otherwise, that may
result from the use.

If these terms are not acceptable to you, then you have NO license 
to use or test EXPR.VBX. You should IMMEDIATELY DELETE it from
your disks.

