[racket] Basic inquiry

This one and the following ones in the series might actually be better:
http://www.youtube.com/watch?v=T4Myub8sJH0

On Sat, May 12, 2012 at 3:03 PM, Laurent <laurent.orseau at gmail.com> wrote:

> Hi Saad,
>
> I don't know if this is advisable in general, and hopefully I'm not making
> a rookie teacher mistake here, but it seems that in your case you could use
> some videos to get you started with the basics:
> For example: http://www.youtube.com/watch?v=IwpnDJ45yLA
>
> There might be some little differences with the current version of
> DrRacket though.
> Other videos:
> http://www.youtube.com/results?q=drracket
>
> This should help you start a little. After that, for the programming part,
> it's probably better if you stick to HtDP.
>
> Cheers,
> Laurent
>
>
> On Sat, May 12, 2012 at 2:35 PM, saad bashir <bashir.saad at gmail.com>wrote:
>
>> Dear Matthias,
>>
>> Thank you for replying to me.  I am sure this is laughably basic for you.
>>
>> I got what you wrote.  I know string-ith extracts the letter.  My
>> question is how to use it. I have tried various ways of writing both in the
>> def and interaction sections but have not worked out.  Even consulting the
>> Helpdesk has not helped as it does not tell me how to use the fucntion.
>>
>> Sorry if I am being very thick. I really want to do it right.
>>
>> Saad
>>
>>
>> On Fri, May 11, 2012 at 11:47 PM, Matthias Felleisen <
>> matthias at ccs.neu.edu> wrote:
>>
>>>
>>> The beginning of section 2.1.3 looks like this:
>>>
>>>
>>> > All other operations concerning strings consume or produce data other
>>> than strings. Here are some examples:
>>> >       • string-length consumes a string and produces a (natural)
>>> number;
>>> >
>>> >       • string-ith consumes a string s and extracts the one-character
>>> substring located at the ith position (counting from 0); and
>>> >
>>> >       • number->string consumes a number and produces a string.
>>> >
>>> > Also look up substring and find out what it does.
>>>
>>> Which function do you think extracts a "letter" from a string? [[You can
>>> follow the links for the function names. Perhaps it is easier to read the
>>> docs.]]
>>>
>>> -- Matthias
>>>
>>>
>>>
>>>
>>> On May 11, 2012, at 4:22 PM, saad bashir wrote:
>>>
>>> > I am back again.  I had a basic inquiry and your help got me started.
>>> >
>>> > My problem is as follows:
>>> >
>>> > I have just started to work through 2Htdp (i.e. the second edition)
>>> that you had guided me to. Having gone through the prologue I am now on the
>>> second chapter, "Fixed-size data."  But have got stuck almost at the start.
>>>  I have successfully done the first two exercises but have hit a road block
>>> on exercise 3 (section 2.1.3 "Mixing it up").  I do not know what
>>> instruction to use to insert or extract a letter from the ith position.  I
>>> think I am doing something wrong when trying to look up things in Helpdesk.
>>> Please help.
>>> >
>>> > Saad
>>> >
>>> > On Fri, Apr 27, 2012 at 8:32 PM, Danny Yoo <dyoo at cs.wpi.edu> wrote:
>>> > On Fri, Apr 27, 2012 at 11:27 AM, saad bashir <bashir.saad at gmail.com>
>>> wrote:
>>> > > Your help was great.  Things are working now.  And a great thank you
>>> for
>>> > > leading me to the 2d edition of How to Design Programs.  I had not
>>> known
>>> > > about it.
>>> >
>>> >
>>> > Glad to hear that it's working for you now!  Please feel free to
>>> > continue to ask questions on the mailing list; we'll be happy to help.
>>> >
>>> > ____________________
>>> >  Racket Users list:
>>> >  http://lists.racket-lang.org/users
>>>
>>>
>>
>> ____________________
>>  Racket Users list:
>>  http://lists.racket-lang.org/users
>>
>>
>
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