check this

[Aldin]

Hi
see this code

#define	MAX_LINE_LENGTH		1024
#define	MAX_TOKEN_LENGTH	32

typedef struct max_min
{
	char maximum[MAX_TOKEN_LENGTH];
	char minimum[MAX_TOKEN_LENGTH];
} m_and_m;

enum data_type{enumber};

in your main program did this

m_and_m max_number;
	FILE *fp;
	int result;
	/*Open input file*/
	fp = fopen("read.csv","r");
	if (fp != NULL)
	{
	max_number = get_max_min(fp,11,5,enumber);
		rewind(fp);
		result = 0;
	}

this the file function

m_and_m *get_max_min(FILE *fp,unsigned start_from_line,unsigned start_from_column,enum data_type dtype)
{
	m_and_m *result;
	unsigned i;
	char current_max[MAX_TOKEN_LENGTH],current_min[MAX_TOKEN_LENGTH],*token;
	char current_line[MAX_LINE_LENGTH];

	/*Use fgets to get one line prior to the desired start line*/
	for (i = 0;i < start_from_line - 1;i++)
	{
		fgets(current_line,MAX_LINE_LENGTH,fp);
	}
	
	/*While there are lines to read*/
	while (fgets(current_line,MAX_LINE_LENGTH,fp))
	{
		/*Read tokens using strtok until you get to the desired start column*/
		i = 0;
		token = strtok(current_line,",");
		while (token != NULL && i < start_from_column - 1)
		{
			token = strtok(NULL,",");
			i++;
		}
		/*Do the actual comparisons to find current_max and current_min*/
		switch (dtype)
		{
		
		case (enumber) :
			printf ("Comparing numbers.\n");
			strcpy(current_max,compare_number(current_max,token));
			strcpy(current_min,compare_number(current_min,token));
			break;
		default :
			fprintf (stderr,"Undefined data type.\n");
			break;
		}
	}

	/*Store the result in an m_and_m type variable and return it*/
	result = (m_and_m *)malloc(sizeof(m_and_m));
	if (result != NULL)
	{
		strcpy(result->maximum,current_max);
	//	strcpy(result->minimum,current_min);
	}
	else
	{
		fprintf(stderr,"Failed to allocate memory.\n");
	}
	return (result);

}

now if you want to buit you max and min function.

char	*compare_number(char *first_number,char *second_number)
{
	char *result;

	
	return (result);
}

how you can build the above function copmare number

[Narue]

Hmm, I would say sscanf would be your best bet for a quick solution:

char	*compare_number(char *first_number,char *second_number)
{
  char *result;
  int x, y;

  sscanf ( first_number, "%d", &x );
  sscanf ( second_number, "%d", &y );

  return x < y ? first_number : second_number;
}

Naturally, you'll need to modify that to fit the needs of your code (I didn't test it) and add error checking.

[Aldin]

Hi Narue
thank you for your help.
I am not sure if it is the right.

you'll need to modify that to fit the needs of your code (I didn't test it) and add error checking.

what do you mean add error checking.

thanks in advance

[Narue]

>what do you mean add error checking
The return value of sscanf will tell you if the conversion worked. If it didn't then the token wasn't a valid integer and you need to fix the error in your code that causes it to be invalid.

[Fasola]

>what do you mean add error checking
The return value of sscanf will tell you if the conversion worked. If it didn't then the token wasn't a valid integer and you need to fix the error in your code that causes it to be invalid.

there she goes...on the ball!

:mrgreen:

p.s. oh and its about time you got a decent avatar....hehehe

[Aldin]

Hi agian
It did not work with me, I amend to return the value but it not.

sscanf

[Narue]

>It did not work with me
That's an absolutely useless statement. If you want help, provide as much information as to how it doesn't work as you possibly can.