Fwd: [Tutor] problem with stirng.find

[Liam Clarke]

---------- Forwarded message ----------
From: Liam Clarke <cyresse at gmail.com>
Date: Wed, 24 Nov 2004 19:45:58 +1300
Subject: Re: [Tutor] problem with stirng.find
To: Gregor Lingl <glingl at aon.at>


In the above

>I get the following string (print s) :
>"\xffS!AAAA\xfe0.005\r\n\xffS!AAAA\xfe0.005\r\n"

>When I do

>Import string
>Print string.find(s,"S!A")

>It prints: 11

I have no idea what's happening, but if you remove the special characters - i.e.

"<\xff>S!AAAA<\xfe>0.005<\r\n><\xff>S!AAAA<\xfe>0.005<\r\n>"

x="S!AAAA0.005S!AAAA0.005"

then x[:11]="S!AAAA0.005"
and  x[11:]="S!AAAA0.005"

Go figure.




On Tue, 23 Nov 2004 08:41:48 +0100, Gregor Lingl <glingl at aon.at> wrote:
>
>
> Isr Gish schrieb:
>
> >Fabian von Berlepsch"<pub at berlepsch.de> wrote:
> >   >I am using pyserail for reading the serial port
> >   >I get the following string (print s) :
> >   >"\xffS!AAAA\xfe0.005\r\n\xffS!AAAA\xfe0.005\r\n"
> >   >
> >   >When I do
> >   >
> >   >Import string
> >
> >...
> >
> > functions in the string module, are now available as string methods.
> >
> >   >Print string.find(s,"S!A")
> >   >
> >   >It prints: 11
> >
> >The find method (function) returns the index where the substring was found. I'm not sure what you expected to happen.
> >
> >
> First I was surprised to find
>
>  >>> for c in "\xffS!AAAA\xfe0.005\r\n\xffS!AAAA\xfe0.005\r\n":
>     c,ord(c)
>
> ('\xff', 255)
> ('S', 83)
> ('!', 33)
> ('A', 65)
> ('A', 65)
> ('A', 65)
> ('A', 65)
> ('\xfe', 254)
> ('0', 48)
> ('.', 46)
> ('0', 48)
> ('0', 48)
> ('5', 53)
> ('\r', 13)
> ('\n', 10)
> ('\xff', 255)
> ('S', 83)
> ('!', 33)
> ('A', 65)
> ('A', 65)
> ('A', 65)
> ('A', 65)
> ('\xfe', 254)
> ('0', 48)
> ('.', 46)
> ('0', 48)
> ('0', 48)
> ('5', 53)
> ('\r', 13)
> ('\n', 10)
>  >>> "\xffS!AAAA\xfe0.005\r\n\xffS!AAAA\xfe0.005\r\n"[11:14]
> '05\r'
>
> So I checked if find indeed returned 11:
>
>  >>> "\xffS!AAAA\xfe0.005\r\n\xffS!AAAA\xfe0.005\r\n".find("S!A")
> 1
>  >>> "\xffS!AAAA\xfe0.005\r\n\xffS!AAAA\xfe0.005\r\n".find("S!A",2)  #
> next occurrence
> 16
>  >>>
>  That's ok, isn't it?
>
> Gregor
>
>
>
> _______________________________________________
> Tutor maillist  -  Tutor at python.org
> http://mail.python.org/mailman/listinfo/tutor
>


--
'There is only one basic human right, and that is to do as you damn well please.
And with it comes the only ba>>>sic human duty, to take the consequences.


-- 
'There is only one basic human right, and that is to do as you damn well please.
And with it comes the only basic human duty, to take the consequences.