Help with replacing part of a "string"

eagletalontim · 2014-11-28 18:27

Hello all again! I am attempting to modify a DAT variable before it is sent to the server, but I can't seem to get the DATAHERE to replace with a number that is calculated.

CON
  _clkmode = xtal1 + pll16x     
  _xinfreq = 5_000_000

  CR            = $0D
  LF            = $0A

DAT
  DataSeg1      byte  "GET /tims/post.php?data=DATAHERE HTTP/1.1", CR, LF, {
}                     "Host: www.example.com", CR, LF, {
}                     "User-Agent: Wiz5100", CR, LF, CR, LF, $0

OBJ
  str             : "STRINGS2"
  pst             : "Parallax Serial Terminal"

VAR
  byte str_test[255]
  byte new_str[255]
  byte value

PUB Main | strh

  pst.Start(115_200)      
  pause(5000)

  value := (12345 + 12345) / 2

  strh := @DataSeg1
  bytefill(@str_test, 0, 255)
  bytemove(@str_test, strh, strsize(strh))
  strh := str.StrReplace(@str_test, string("DATAHERE"), value)  ' *******  Lost Here????
  pst.str(strh)

PRI pause(Duration)  
  waitcnt(((clkfreq / 1_000 * Duration - 3932) #> 381) + cnt)
  return

I can replace the line in question with :

strh := str.StrReplace(@str_test, string("DATAHERE"), string("12345"))

and it works exactly as needed.

How can I replace the DATAHERE with a calculated number?

SRLM · 2014-11-28 18:37

Can't you construct the number as a string (in a "scratchpad" area), then use StrReplace with the calculated string?

eagletalontim · 2014-11-28 18:46

Not sure I quite understand. The number that will be calculated is the pulse width of a flashing IR LED which will change with every pulse. How could I construct the number as a string?

Cluso99 · 2014-11-28 18:58

Kye wrote a good set of string handling routines. IIRC they are in the OBEX and are worth looking at, as well as using them.

localroger · 2014-11-28 19:08

If you want to output the number as ASCII text, you have to convert it to a string of ASCII characters. The typical Propeller libraries don't do this very well; instead of having generic string functions they have methods like "dec" built into every output driver.

I have written a library that does what you need. It didn't get a lot of attention but you can find it here:

http://forums.parallax.com/showthread.php/148937-Concept-Test-General-Purpose-String-Output-Formatting

eagletalontim · 2014-11-28 19:09

Yep, that was it. Just found it. I knew there was a function somewhere. Already had it, just needed to use it.

SRLM · 2014-11-28 19:13

You want to insert the decimal representation of a variable into a string, right? Then the source of the number doesn't really matter. All you need is a variable that has the number, and a function to convert that into a string. Such can be found, for example, here, under integer to decimal:

PUB integerToDecimal(number, length) '' 5 Stack Longs

'' ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
'' // Converts an integer number to the decimal string of that number padded with zeros.
'' //
'' // Returns a pointer to the converted string.
'' //
'' // Number - A 32 bit signed integer number to be converted to a string.
'' // Length - The length of the converted string, "+" or "-" will be concatenated onto the head of converted string.
'' ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

  length := (10 - ((length <# 10) #> 0))

  decimalString := "+"
  if(number < 0)
    decimalString := "-"

  if(number == negx)
    bytemove(@decimalString, string("-2147483648KA"), 11)

  else
    repeat result from 10 to 1
      decimalString[result] := ((||(number // 10)) + "0")
      number /= 10

  decimalString[length] := decimalString
  return @decimalString[length]

FDS+ also has a decimal to string function, although you'd have to modify it to write to a buffer instead of the tx() function.

PUB dec(value) | i, x

'' Print a decimal number

  x := value == NEGX                                                            'Check for max negative
  if value < 0
    value := ||(value+x)                                                        'If negative, make positive; adjust for max negative
    tx("-")                                                                     'and output sign

  i := 1_000_000_000                                                            'Initialize divisor

  repeat 10                                                                     'Loop for 10 digits
    if value => i                                                               
      tx(value / i + "0" + x*(i == 1))                                          'If non-zero digit, output digit; adjust for max negative
      value //= i                                                               'and digit from value
      result~~                                                                  'flag non-zero found
    elseif result or i == 1
      tx("0")                                                                   'If zero digit (or only digit) output it
    i /= 10                                                                     'Update divisor

Phil Pilgrim (PhiPi) · 2014-11-28 21:10

Chip's SimpleNumbers object that's part of the Spin library will do what you want.

-Phil

Help with replacing part of a "string"

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