NXC: string-upcase? string-downcase?

[HaWe]

hi,
do we already have functions for string upcase/downcase in NXC?
I know that there's toupper but it's designed for a single char, not for strings (CMIIW)

[nxtboyiii]

just do this:

Code: Select all

task main()
{
 string s="lorem ipsum";
 char s_data[];
 byte length=StrLen(s);
 ArrayInit(s_data,0,length);
 StrToByteArray(s,s_data);
 for(int c=0; c < ArrayLen(s_data); c++)
 {
  toupper(s_data[c]);
 }
 ByteArrayToStr(s_data);
}

[afanofosc]

I don't think that will work.

Try this:

Code: Select all

task main()
{
  string s="lorem ipsum";
  TextOut(0, LCD_LINE1, s);
  for(int c=0; c < strlen(s); c++)
    s[c] = toupper(s[c]);
  TextOut(0, LCD_LINE2, s);
  Wait(SEC_5);
}

John Hansen

[HaWe]

yes, this
for(int c=0; c < strlen(s); ++c) s = toupper(s[c]);
is just what I am already doing!

thank you!

[spillerrec]

If tolower and toupper were native firmware operations you could have used them on arrays too, but it is not the case. Well, there isn't a function to do this in C either AFAIK...

Any particular reason you are looking for such functions? Do you need to do this operation as fast as possible, or just curious if there was a better way to do it?

This version is a bit more efficient:

Code: Select all

for( int i=strlen(s); i>=0; i-- )
   s[i] = toupper(s[i]);

Instead of checking the array length each time, it will only be done once in this hence the performance boost. (33%, 22 msec compared to 33 msec with "Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor ".)

If you really want performance try this:

Code: Select all

  {
     int i = strlen( s );
     unsigned char c;
     
     loop_start:
     asm{
       brtst LTEQ, loop_end, i
       sub i, i, 1
       
       index c, s, i
       brcmp LT, loop_start, c, 97
       brcmp GT, loop_start, c, 122
       
       sub c, c, 32
       replace s, s, i, c
       
       jmp loop_start
       loop_end:
     }
  }

This is ~66% (9 msec) compared to the original and even faster if the string contains a lot of non-lower case character as it only overwrites the character if it indeed is lower case.

[HaWe]

no, thanks, I'm programming in NXC, never in NBC

(speed is no issue, and if it was, I would wish the fw would work faster)

;)

[afanofosc]

See this post:

https://sourceforge.net/apps/phpbb/mind ... 150#p12086

uplow.nxc

(393 Bytes) Downloaded 293 times

John Hansen

[HaWe]

sry, what is this link for?

[mightor]

Doc,

Did you read the post John linked?

- Xander

[HaWe]

yes of course but I didn't understand what this is for (asm, chunkID,...?)
does it mean there now are new functions in the API called UpperCase and LowerCase for strings?