Thread: Problem with function!

Hello to all, newbie here.

I need help with my function. Here is the code for the function:

Code:

char content_scan( char sequence)
    {
        int x ;
        
        for(x=0 ; x < (strlen(sequence)) ; x++)
            {
                while( sequence[x] )
                    {
                        if( sequence[x] == 'U' ) 
                            {
                                return "RNA" ;
                                break ;
                            }
                        else if (sequence[x] == 'A' || x == 'C' || x == 'G' || x == 'T')
                            {
                                return "DNA" ;
                                break ;
                            }
                        else
                            {
                                return "PROTEIN" ;
                                continue ;
                            }
                    }
            }
    }

I am trying to return the output to the variable "loadedSequences[nSequences].type" which is a character array with the following statement:

Code:

loadedSequences[nSequences].type = content_scan(loadedSequences[nSequences].data) ;

The argument for the function will be a long string of letters.

Any help would be great.

Still receiving errors. Here are the errors:

beta_seqTool.c: In function ‘content_scan’:
beta_seqTool.c:14: warning: passing argument 1 of ‘strlen’ makes pointer from integer without a cast
beta_seqTool.c:16: error: subscripted value is neither array nor pointer
beta_seqTool.c:18: error: subscripted value is neither array nor pointer
beta_seqTool.c:23: error: subscripted value is neither array nor pointer
beta_seqTool.c: In function ‘main’:
beta_seqTool.c:128: warning: passing argument 1 of ‘content_scan’ makes integer from pointer without a cast

Code:

int content_scan( char sequence)
    {
        int x ;
        
14        for(x = 0 ; x < strlen(sequence) ; x++)
            {
16                while( sequence[x] )
                    {
18                        if( sequence[x] == 'U' ) 
                            {
                                return 1 ; // RNA
                                break ;
                            }
23                        else if (sequence[x] == 'A' || x == 'C' || x == 'G' || x == 'T')
                            {
                                return 2 ; // DNA 
                                break ;
                            }
                        else
                            {
                                return 3 ; // PROTEIN
                                continue ;
                            }
                    }
            }
    }

Code:

128     loadedSequences[nSequences].type = content_scan(loadedSequences[nSequences].data) ;

Also, is there a way I can return a string (i.e DNA, RNA, or PROTEIN as my value for loadedSequences[nSequences].type?

Sorry, didn't see your post. So if i use the address as my argument things should work fine?

heres the code:

Code:

10    char content_scan( (char &)sequence)
    {
        int x ;
        
        for(x = 0 ; x < strlen(sequence) ; x++)
            {
                while( sequence[x] )
                    {
                        if( sequence[x] == 'U' ) 
                            {
                                return "RNA" ;
                                break ;
                            }
                        else if (sequence[x] == 'A' || x == 'C' || x == 'G' || x == 'T')
                            {
                                return "DNA" ;
                                break ;
                            }
                        else
                            {
                                return "PROTEIN" ;
                                continue ;
                            }
                    }
            }
    }                

char *address4content_scan = &loadedSequences[nSequences].data[0] ;
                                   
133    loadedSequences[nSequences].type = content_scan(address4content_scan) ;

Still receiving some errors:

beta_seqTool.c:10: error: syntax error before ‘(’ token
beta_seqTool.c: In function ‘main’:
beta_seqTool.c:133: error: incompatible types in assignment


Any suggestions?

You really should learn C before you start messing around with the building blocks of life as we know it...

Code:

#include <stdio.h>
#include <string.h>

typedef enum { RNA, DNA, Protein, Unknown } SequenceType;

static const char *const NucleotideCodes = "ACGTU";

SequenceType content_scan(const char *sequence)
{
   // First we'll see if it's a protein.
   const char *p = sequence;

   // Go through each code.
   while (p && *p != 0)
   {
      // If the current code is not a nucleotide, obviously it's an amino
      // acid chain and therefore a protein.
      if (strchr(NucleotideCodes, *p) == NULL)
         return Protein;
      ++p;
   }

   // Not a protein, but a nucleotide sequence; only differentiator is
   // uracil vs. thymine.
   // Reset convenience pointer
   p = sequence;
   while (p && *p != 0)
   {
      if (*p == 'U') return RNA;

      if (*p == 'T') return DNA;

      ++p;
   }
   return Unknown;
}

int main()
{
   const char *sequences[] = {
      "AGCGAACUGCCCG", "AGCGAACTGCCCG", "AGMLAHA" } ;

   int i = 0;
   for (; i < (sizeof(sequences) / sizeof(sequences[0])); ++i)
   {
      printf("Result for %s: ", sequences[i]);

      switch(content_scan(sequences[i]))
      {
      case RNA:
         printf("RNA\n");
         break;
      case DNA:
         printf("DNA\n");
         break;
      case Protein:
         printf("Protein\n");
         break;
      case Unknown:
      default:
         printf("Unknown\n");
         break;
      }

   }

   return 0;
}

Thanks for the help.

Question: Why couldn't I return the string "DNA" etc directly? Why use "void"?

Can anyone see why this is returning "PROTEIN" when the first is DNA (all ACGT) ?

Code:

void content_scan( char * sequence, char * out_field )
    {
        int x ;
        
        for(x = 0 ; x < strlen(sequence) ; x++)
            {
                while( sequence[x] )
                    {
                        if( sequence[x] == 'U' ) 
                            {
                                strcpy(out_field, "RNA") ;
                                return ;
                            }
                        else if (sequence[x] != 'A' || sequence[x] != 'C' || sequence[x] != 'G' || sequence[x] != 'T' || sequence[x] != EOF || sequence[x] != '\n' )
                            {
                                strcpy(out_field, "PROTEIN") ;  
                                return ; 
                            }
                        else
                            {
                                strcpy(out_field, "DNA" ) ;
                                return ;
                            }
                    }
            }
    }