[Caml-list] Scanf.sscanf surprised me

[Caml-list] Scanf.sscanf surprised me

[Francois Berenger]

This example line and scanning format work:

# let line = "active_ZINC01535869 
0.470,0.389,0.479,0.453,0.470,0.631,0.562,0.590,0.677,0.558,0.379";; 
                                                       val line : string =
   "active_ZINC01535869 
0.470,0.389,0.479,0.453,0.470,0.631,0.562,0.590,0.677,0.558,0.379"
# Scanf.sscanf line "%s %f,%f,%f,%f,%f,%f,%f,%f,%f,%f,%f" (fun name s1 
s2 s3 s4 s5 s6 s7 s8 s9 s10 s11 -> (name, s1, s2, s3, s4, s5, s6, s7, 
s8, s9, s10, s11));;
- : string * float * float * float * float * float * float * float *
     float * float * float * float
=
("active_ZINC01535869", 0.47, 0.389, 0.479, 0.453, 0.47, 0.631, 0.562, 
0.59, 0.677, 0.558, 0.379)

This one doesn't:

# let line = 
"active_ZINC01535869,0.470,0.389,0.479,0.453,0.470,0.631,0.562,0.590,0.677,0.558,0.379";; 
                                                          val line : 
string =
 
"active_ZINC01535869,0.470,0.389,0.479,0.453,0.470,0.631,0.562,0.590,0.677,0.558,0.379"
# Scanf.sscanf line "%s,%f,%f,%f,%f,%f,%f,%f,%f,%f,%f,%f" (fun name s1 
s2 s3 s4 s5 s6 s7 s8 s9 s10 s11 -> (name, s1, s2, s3, s4, s5, s6, s7, 
s8, s9, s10, s11));;
Exception: End_of_file.

I am quite surprised.
I was expecting the first separator being a space or a coma
to behave the same.

-- 
Best regards,
Francois Berenger.

Re: [Caml-list] Scanf.sscanf surprised me

[Robert Roessler]

Francois Berenger wrote:
> This example line and scanning format work:
>
> # let line = "active_ZINC01535869
> 0.470,0.389,0.479,0.453,0.470,0.631,0.562,0.590,0.677,0.558,0.379";;
>                                                        val line : string =
>    "active_ZINC01535869
> 0.470,0.389,0.479,0.453,0.470,0.631,0.562,0.590,0.677,0.558,0.379"
> # Scanf.sscanf line "%s %f,%f,%f,%f,%f,%f,%f,%f,%f,%f,%f" (fun name s1
> s2 s3 s4 s5 s6 s7 s8 s9 s10 s11 -> (name, s1, s2, s3, s4, s5, s6, s7,
> s8, s9, s10, s11));;
> - : string * float * float * float * float * float * float * float *
>      float * float * float * float
> =
> ("active_ZINC01535869", 0.47, 0.389, 0.479, 0.453, 0.47, 0.631, 0.562,
> 0.59, 0.677, 0.558, 0.379)
>
> This one doesn't:
>
> # let line =
> "active_ZINC01535869,0.470,0.389,0.479,0.453,0.470,0.631,0.562,0.590,0.677,0.558,0.379";;
>                                                           val line :
> string =
>
> "active_ZINC01535869,0.470,0.389,0.479,0.453,0.470,0.631,0.562,0.590,0.677,0.558,0.379"
>
> # Scanf.sscanf line "%s,%f,%f,%f,%f,%f,%f,%f,%f,%f,%f,%f" (fun name s1
> s2 s3 s4 s5 s6 s7 s8 s9 s10 s11 -> (name, s1, s2, s3, s4, s5, s6, s7,
> s8, s9, s10, s11));;
> Exception: End_of_file.
>
> I am quite surprised.
> I was expecting the first separator being a space or a coma
> to behave the same.

The specification of scanf "%s" is "Any number of non-whitespace 
characters, stopping at the first whitespace character found".

So, perhaps not that surprising?

Regards,
-- 
Robert Roessler

Re: [Caml-list] Scanf.sscanf surprised me

[Gabriel Scherer]

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Use "%s@,%f..." to specify (with @) that the string should stop at the
first comma.


On Tue, Oct 8, 2013 at 5:28 AM, Robert Roessler <roessler@rftp.com> wrote:

> Francois Berenger wrote:
>
>> This example line and scanning format work:
>>
>> # let line = "active_ZINC01535869
>> 0.470,0.389,0.479,0.453,0.470,**0.631,0.562,0.590,0.677,0.558,**0.379";;
>>                                                        val line : string =
>>    "active_ZINC01535869
>> 0.470,0.389,0.479,0.453,0.470,**0.631,0.562,0.590,0.677,0.558,**0.379"
>> # Scanf.sscanf line "%s %f,%f,%f,%f,%f,%f,%f,%f,%f,%f,**%f" (fun name s1
>> s2 s3 s4 s5 s6 s7 s8 s9 s10 s11 -> (name, s1, s2, s3, s4, s5, s6, s7,
>> s8, s9, s10, s11));;
>> - : string * float * float * float * float * float * float * float *
>>      float * float * float * float
>> =
>> ("active_ZINC01535869", 0.47, 0.389, 0.479, 0.453, 0.47, 0.631, 0.562,
>> 0.59, 0.677, 0.558, 0.379)
>>
>> This one doesn't:
>>
>> # let line =
>> "active_ZINC01535869,0.470,0.**389,0.479,0.453,0.470,0.631,0.**
>> 562,0.590,0.677,0.558,0.379";;
>>                                                           val line :
>> string =
>>
>> "active_ZINC01535869,0.470,0.**389,0.479,0.453,0.470,0.631,0.**
>> 562,0.590,0.677,0.558,0.379"
>>
>> # Scanf.sscanf line "%s,%f,%f,%f,%f,%f,%f,%f,%f,%**f,%f,%f" (fun name s1
>> s2 s3 s4 s5 s6 s7 s8 s9 s10 s11 -> (name, s1, s2, s3, s4, s5, s6, s7,
>> s8, s9, s10, s11));;
>> Exception: End_of_file.
>>
>> I am quite surprised.
>> I was expecting the first separator being a space or a coma
>> to behave the same.
>>
>
> The specification of scanf "%s" is "Any number of non-whitespace
> characters, stopping at the first whitespace character found".
>
> So, perhaps not that surprising?
>
> Regards,
> --
> Robert Roessler
>
>
>
> --
> Caml-list mailing list.  Subscription management and archives:
> https://sympa.inria.fr/sympa/**arc/caml-list<https://sympa.inria.fr/sympa/arc/caml-list>
> Beginner's list: http://groups.yahoo.com/group/**ocaml_beginners<http://groups.yahoo.com/group/ocaml_beginners>
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>

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Re: [Caml-list] Scanf.sscanf surprised me

[Eric Cooper]

To paraphrase Jamie Zawinski:

    Some people, when confronted with a problem, think "I know, I'll use
    scanf." Now they have two problems.

-- 
Eric Cooper             e c c @ c m u . e d u