If there a basic4ppc VB Eval()

T

tinmanjo

Member

Licensed User

• Apr 18, 2010

• #1

Im trying to convert a sum say (1*6+3) as a string

in vb you use :-

sum="1*6+3"
Eval(sum)

which evalutes and calculates. =9 etc

is there a way to do this in Basic4ppc?

 

Erel

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• Apr 18, 2010

• #2

There is a module file that implements it.
See the attached sample (download both files).

 

Attachments

• Solver.sbp

  6.2 KB · Views: 197
• EvalModule.bas

  2.7 KB · Views: 200

T

tinmanjo

Member

Licensed User

• Apr 18, 2010

• #3

Thanks Erel,

Ive tried running the example but im getting syntax errors, and the module has some, was this for an earlier version than 6.80?

 

agraham

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• Apr 18, 2010

• #4

Forget the demo (I don't understand it either ) and try just using the Eval Sub like

result = EvalModule.Eval("1+3*12")

 

Erel

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• Apr 18, 2010

• #5

I think that the problem is that this code was adapted to v6.90 with the variables typing.
You can find the same code that will work with your version under the samples folder.
It is located under c:\program files\anywhere software\basic4ppc desktop\samples

Forget the demo (I don't understand it either

)

Click to expand...

I don't understand as well it is an implementation of this:
Cramer's rule - Wikipedia, the free encyclopedia

which solves linear equations.

 

agraham

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• Apr 21, 2010

• #6

I remembered that Rioven posted http://www.b4x.com/forum/code-samples-tips/1207-scientific-math-text-input-evaluator.html that is quite capable and supports functions. It could easily be made into a module.