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Home / Modeling / The Basic of Modeling / Entry by Mathematical Expressions

Entry by Mathematical Expressions

Mathematical expressions can be entered in the entry fields of various input dialogs.

The exponential representation like 1.0e-3 is acceptable. The power must be an integer. Otherwise, it will cause an error. The "e" is case-insensitive.

 

 

 

The usable operators and functions are listed below.

* Both upper-case and lower-case letters can be used for them.

 

The priority of operations follow that of Microsoft VB/VBA. The operations upper in the list below has the higher priority.

Symbols

Notes

^

Power

*

/

Multiplication

Division

+

-

Addition

Subtraction

=

<>

<

<=

>

>=

Relational operations

 

  • <> means "not equal to".

  • If it is TRUE, the value is -1.

  • If it is FALSE, the value is 0.

And

Logical conjunction

The bitwise AND of fraction-rounded integers.

Or

Logical disjunction

The bitwise OR of fraction-rounded integers.

 

Functions

Notes

Sin

Sine. The unit of the argument is radian.

Cos

Cosine. The unit of the argument is radian.

Tan

Tangent. The unit of the argument is radian.

Atn

Arctangent. The unit of the return value is radian.

Log

The natural logarithm with base "e".

Sqr

Square root.

Abs

Absolute value of the argument.

F_IF

Conditional function.

 

There are 3 arguments. The second argument returns unless the first argument is "0.0".

The third argument returns if the first argument is "0.0". The separator is ",".

  • The first argument: Enter the relational operations, the logical operation or the mathematical expressions.

  • The second argument: The value to return unless the first argument is "0.0".

  • The third argument: The value to return if the first argument is "0.0".

 

Example: F_IF(val_a<=2, val_a*2,val_b*1.5)

If val_a is less than or equal to 2, val_a*2 returns.

If val_a is more than, val_b*1.5 returns.

 

 

Commonly used but unlisted operations/functions

Notations

Notes

π

Use a preregistered variable "pi", or the formula "4.0*Atn(1.0)".

Secant

Use the formula "1/Cos(X)".

Cosecant

Use the formula "1/Sin(X)".

Cotangent

Use the formula "1/Tan(X)".

Arcsine

Use the formula Atn(X/Sqr(-X*X+1))

Arccosine

Use the formula Atn(-X/Sqr(-X*X+1))+2*Atn(1)

Logarithm of non-"e" base

Use the formula LogN(X) = Log(X) / Log(N)

Power

Pow(X,Y) = X ^ Y