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ExpressionEvaluator

Written by Andrew Graham

This library includes an Evaluator object that can evaluate arithmetic expressions.

List of types:

This class contains an arithmetic expression evaluator.
It supports the arithmetic sub-set of the full Basic4android language.

Operators in precedence order are

^ : exponent
* / mod : multiply, divide and modulus, % is also accepted for mod
+ - : add and subtract

Functions supported are

COS(r), SIN(r), TAN(r), ACOS(n), ASIN(n), ATAN(n) : radians
COSD(d), SINDd), TANDd), ACOSD(n), ASIND(n), ATAND(n) : degrees
LN(n) base e, LOG(n) base 10, LOGARITHM(n, base) any base
SQRT(n), FLOOR(n), ABS(n), MAX(n1, n2), MIN(n1, n2), POWER(n, exp), ROUND(n)

Constants recognised are
CPI : Pi
CE : e

Twenty-six case-insensitive variables are supported named from "A" to "Z" and must be intialised with the required value before being used in an evaluation.
Although the actual variable names are a single letter longer names are accepted but only the initial letter is used to identify the variable.
Variable values are maintained across evaluations.

Events:

None

Members:

Error As String [read only]

ErrorFlag As Boolean [read only]

Evaluate (expression As String) As Double

EvaluateAndSave (expression As String, var As String) As Double

GetGlobal (var As String) As Double

Initialize

SetGlobal (var As String, value As Double)

Version As Double [read only]

Members description:

ExpressionEvaluator

Written by Andrew Graham

List of types:

Evaluator

Events:

Members:

Members description:

Error As String [read only]

ErrorFlag As Boolean [read only]

Evaluate (expression As String) As Double

EvaluateAndSave (expression As String, var As String) As Double

GetGlobal (var As String) As Double

Initialize

SetGlobal (var As String, value As Double)

Version As Double [read only]