I bet the answer to my problem is hidden somewhere in these forums as this seems to be a fairly common question, yet after literally 2 days of searching for an answer I can't find it so please bare with me.

What I'm trying to do here is to read a .csv file, 200 rows, 2 columns, standard formation, comma separated. Then I want to store the contents of the file in an array and be able to manipulate data from that point on. This is the code I've come up with so far.

#include "stdafx.h"
#include "conio.h."
#include "stdlib.h"
#include "string.h"

int _tmain(int argc, _TCHAR* argv[])
{
	struct
	{
		char grade[10];
		char name[15];
	}	student[200];

	FILE *fp;
	char count[200];

    int i=0,j;

    fp=fopen("students.csv","r");
	if(fp==NULL)
		{
			printf("Could not properly load file!\n");
			getch();
			exit(8);
		}
	else
		{
			printf("File openned and loaded properly\n\n");
		}

    while(fgets(count,20,fp)!=NULL)
			 {
			 strcpy(student[i].grade,strtok(count,","));
                         strcpy(student[i].name,strtok(count,","));
                         ++i;
			 }
			 
    for(j=0;j<200;j++)
			 {
				 printf("%s\t",&student[j]);
				
			 }

	printf("\nClosing file\n");
    fclose (fp);


	getch();
	return 0;
}

The csv file looks pretty much like this:

15.1,John
17.34,Angella
23.31,Jake
82.49,Christy

I know my problem should pretty much be in line 34. At the moment the program does compile and properly outputs the data contained on the first column which is numerical (float). I just have no clue how to parse second column data (the names) into student[].name

Assuming I get to the point that data is properly separated in student[].grade and student[].name I'd like to convert the numerical data from char strings into float numerical data. I understand atof is the way to do but after experimenting with it I can't get it to work, getting strange results no matter how much I tried.

Thanks in advance, please ignore the fact that my code most likely sucks, I'm a complete newbie when it comes to C and programming in general. Also please note that C++ is not an option, only ANSI C is allowed.

line 34: the first parameter to strtok() is supposed to be NULL. It should be a valid string only the first time strtok() is called, which was on line 33.

Ok thats understandable. But how exactly can I parse the second column of the file into the array? (the names part). Was my approach to the problem completely wrong? :S

I understand atof is the way to do but after experimenting with it I can't get it to work, getting strange results no matter how much I tried.

Hi, char array is not string, atof take string as param, put '\0' in the last of char array, probably then it will work
like:
char abc[]={'3','.','5','\0'};
printf("no. is %f",atof(abc));

I decided to rewrite the code, this time instead of playing around with strcpy and strtok I wanted to try fscanf which (from my newbie point of view) would make my life easier dealing with first columns numerical floating point data.

int _tmain(int argc, _TCHAR* argv[])
{
	FILE *fp;
	float numbers[200];
	char name[200];
	int i=0;
	int j=0;
		
	fp=fopen("students.csv","r");


	while(!feof(fp)) 
		{ 
			fscanf(fp, "%f", &numbers[i]);
			fscanf(fp, "%s", &name[i]);
			i++;
		}

	for(j=0;j<200;j++)
		{	
			printf("%f\n",numbers[j]);
			printf("%s\n",name[j]);
		}
	getch();
	return 0;
}

Obviously line15 is wrong, I can tell that much. I just don't know how to fix it :S
Keep in mind data on file is populated in the follow style:

15.1,John
17.34,Angella
23.31,Jake
82.49,Christy
.....

So how should that fscanf look like in order for it to catch the names? I guess somehow reading from comma to carriage return. Or did I completely misunderstood fscanf and doesnt work for char data?

Last little problem, when parsing numbers, I get somewhat strange results, for example 17.34 turns into 17.340001 or 23.31 turns into 23.309998 , why is this happening?

Sorry for my newbish questions and thanks in advance for your answers and patience.

lines 14 and 22: names is not a valid pointer because names is declared wrong on line 5. What you want is this: char name[200][20]; and assume the length of a name will never be more than 20 characters.

I think you can combine lines 14 and 15 like this (untested): fscanf(fp, "%f,%s", &numbers[i], names[i]); >Last little problem, when parsing numbers, I get somewhat strange results, for example 17.34 turns into 17.340001 or 23.31 turns into 23.309998 , why is this happening?

That's the nature of floting point numbers and has to do with powers of 2. Many numbers can not be represented exactly with floats and doubles, which is why you can't test them for equality with the == operator. To get an in-depth explaination you would have to read the IEEE standards, available free on the net.

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