2-Dimensional Dynamic Array

Hi,
I tried to get my program to count the number of rows in the input data file and then output back the same data with 7 columns and however many rows. It's giving me all zeros in the output file though, which isn't supposed to happens since the input file is just random numbers, e.g.:

123.45 111.23 33.45 66.345 43545.54 543.54 5435.43

Could someone take a look at the code?

Code:

	int j , i; 
	int rows = 1;
	float num;
	int c;

	while ((c = fgetc(fp)) != EOF)
	{
		if (c == '\n')
		{
		rows++;
		printf("%d\n", rows);
		}
	}
	
	float **data;
	data = (float**) malloc(rows * sizeof(int));
	for (int i = 0; i < rows; i++)
	{data[i] = (float*)malloc(7*sizeof(int));
	}
	
	//declares array with 7 columns and number of rows in file
	
	for (j=0; j< rows; j++) //repeats for max number of columns
	{
		for (i=0; i< 7; i++)
		{
			fscanf(fp, "%f", &num);
			
			data[j][i] = num;
		}
	}	
	
	
	for(j = 0; j < rows; j++) //repeats for max number of columns
	{
		for (i=0; i< 7; i++)
		{ 
			num = data [j][i];
			
			fprintf(fp2, "%f ", num);
			
		}
		fprintf(fp2, "\n");
	}

Thanks.

Code:

data = (float**) malloc(rows * sizeof(int));

What on earth is this supposed to do?


Quzah.

Oh sorry, those floats are meant to be integers, I was just trying some stuff and I forgot to change it back. Revised code:

Code:

int j , i; 
	int rows = 1;
	float num;
	int c;

	while ((c = fgetc(fp)) != EOF)
	{
		if (c == '\n')
		{
		rows++;
		printf("%d\n", rows);
		}
	}
	
	int **data;
	data = (int**) malloc(rows * sizeof(int));
	for (int i = 0; i < rows; i++)
	{data[i] = (int*)malloc(7*sizeof(int));
	}
	
	//declares array with 7 columns and number of rows in file
	
	for (j=0; j< rows; j++) //repeats for max number of columns
	{
		for (i=0; i< 7; i++)
		{
			fscanf(fp, "%f", &num);
			
			data[j][i] = num;
		}
	}	
	
	
	for(j = 0; j < rows; j++) //repeats for max number of columns
	{
		for (i=0; i< 7; i++)
		{ 
			num = data [j][i];
			
			fprintf(fp2, "%f ", num);
			
		}
		fprintf(fp2, "\n");
	}

The data you want to read in looks like floating point to me. So you want to allocate floats, not ints.

Originally Posted by juice_box

Code:

...
	while ((c = fgetc(fp)) != EOF)
	{
...	
	for (j=0; j< rows; j++) //repeats for max number of columns
	{
		for (i=0; i< 7; i++)
		{
			fscanf(fp, "%f", &num);
			
			data[j][i] = num;
		}
	}

Ignoring your problems with malloc(), you're reading to the end of the file, and then reading some more.