[Tutor] eval func with floating...

[Chanakya Mitra]

c=set(a).intersection(set(check))

 

shouldn’t this be:

 

c=set(a).issubset(set(check))

 

?

 

set(a).intersection(set(check)) will be true as long as only one element appears in both. ie. 15/a8 kill the process and spit out an error instead of asking "error! please use -defined operators-!"

 


Sent: 23 August 2011 12:53
To: tutor at python.org
Subject: Re: [Tutor] eval func with floating...

 

 

On Tue, Aug 23, 2011 at 6:52 AM, Peter Otten <__peter__ at web.de> wrote:

simulacrx wrote:

> check=(1,2,3,4,5,6,7,8,9,"/","*","-","+","(",")","[","]")

You have to quote the digits: 1 is an integer while "1" is a string of
length one:

>>> "1" == 1
False

Also, you forgot the "0".
Note that there's no need to use a tuple as set() will happily accept a
string:

check = set("0123456789/*-+,()")


> while True:
>      a=raw_input("type your query : \n")
>      c=set(a).intersection(set(check))
>
>      if c:
>          print *eval("float(%s)"%a)*
>      else:
>          print "error! please use -defined operators-!"
> -----------------------------
>
> this script works.. but if i type
>
> 15/8
>
> it returns 1.. no floatin'.. i must fix this? can anyone help me?



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I'm not sure if the performance difference would matter, but if you make check a set above your loop there is no need to use the set(check) in the loop when check will do

-- 
Joel Goldstick

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