parsing equations

[munehiro]

hi all,

i have a question.
Given the string '3+2*6' i need to parse it and obtain the result, so
15. Does a module for this operation exists? i need to do simple
operations, but also on floating point numbers.

many thanks

[Diez B. Roggisch]

Re: parsing equations

> i have a question.[color=blue]
> Given the string '3+2*6' i need to parse it and obtain the result, so
> 15. Does a module for this operation exists? i need to do simple
> operations, but also on floating point numbers.[/color]

Use the builtin function eval to evaluate an arbitrary python expression:
[color=blue][color=green][color=darkred]
>>> eval("3+2*6")[/color][/color][/color]
15


Regards,

Diez

[Peter Otten]

Re: parsing equations

Diez B. Roggisch wrote:
[color=blue][color=green]
>> i have a question.
>> Given the string '3+2*6' i need to parse it and obtain the result, so
>> 15. Does a module for this operation exists? i need to do simple
>> operations, but also on floating point numbers.[/color]
>
> Use the builtin function eval to evaluate an arbitrary python expression:
>[color=green][color=darkred]
>>>> eval("3+2*6")[/color][/color]
> 15[/color]

Be aware that this is powerful:
[color=blue][color=green][color=darkred]
>>> eval("cleanMyHa rddisk()")[/color][/color][/color]
'done'

Just to make sure the OP is aware of the inherent danger of the unsuspecting
"arbitrary python expression"...

Peter

[Diez B. Roggisch]

Re: parsing equations

> Be aware that this is powerful:[color=blue]
>[color=green][color=darkred]
>>>> eval("cleanMyHa rddisk()")[/color][/color]
> 'done'
>
> Just to make sure the OP is aware of the inherent danger of the
> unsuspecting "arbitrary python expression"...[/color]

Yup - should have mentioned that.

Diez

[munehiro]

Re: parsing equations

Diez B. Roggisch wrote:[color=blue]
> Use the builtin function eval to evaluate an arbitrary python[/color]
expression:[color=blue]
>
>[color=green][color=darkred]
>>>>eval("3+2*6 ")[/color][/color][/color]


many thanks... it's exactly what i need :)