Thread: Make a matrix from a textfile.. Cant figure how!

Greetings.

I am pretty new to C-programming since I just started 2 weeks ago. I though think its very fun and like to be better at it.

I found something hard to prgram, since I have no idea how it should be written.

Ill try to explain what I did untill now and what I cant get to work.

I have a textfile temperatur.txt with 31 temperatures looking like this:

1 2 5 3 -2 0 2 1 0 4 3 2 0 1...

Another textfile with downpour.txt

-2 2 3 4 1 2 0 0 0 3 5 2 1 0 0 2...

Both files with 31 numbers in.

I loaded both files in with FILE*prt and prt..... scanf.... etc. This is working.

I need to find where there aint no downpour, and find the dates and temperatur for this.
So im setting downpour09[i] == 0, then I know the i´s is the dates and temptabel09[i] is the temperatur those days.

this is the program:

Code:

    for (i = 0; i < 31; i++)
        if(downpour09[i] == 0) //find where there aint no downpour.
        {
            printf("Date[%d]Temperatur[%.f ]\n",i,temptabel09[i]); 
        }

The output is:

Date[2] Temperatur[-2]
Date[1] Temperatur[-3]
Date[-2] Temperatur[-4]
Date[4] Temperatur[-1]
Date[1] Temperatur[0]

But I would like the output to be like a Matrix.

Date 2 temperatur -2
Date 1 temperatur -3
Date -2 temperatur -4
Date 4 temperatur -1
Date 1 temperatur -0

you see my point?

I tried with a simple matrix:

Code:

void main()
{
int matrix[3][2];
int i,j;
   for (i = 0 ; i < 3; i++)
   {
      for(j = 0;j < 2;j++)
     {
      matrix[i][j]=tal;
      tal++;
      printf("%d",tal);
      }
   }
}

the output is: 123456

But I want the output to be
1 2
3 4
5 6

How?

I hope I explained it right and its not to long.

Cheers.

Originally Posted by lovelace

Code:

    for (i = 0; i < 31; i++)
        if(downpour09[i] == 0) //find where there aint no downpour.
        {
            printf("Date[%d]Temperatur[%.f ]\n",i,temptabel09[i]); 
        }

I hope I explained it right and its not to long.

Cheers.

So... take the square brackets out and add a newline at the end of the formatting string in your printf() statement.

Look up printf() in your C Library Documentation, it will give you all the details on how printf() works.

Originally Posted by Subsonics

The output you get is related to how you use printf in this case. You need an extra space in there, then add a new line printf in the outer loop.

Code:

for(i = 0; i < 3; i++) 
{

     for(j = 0; j < 2; j++) 
     {
          var++;
          printf("%d ", var);
     }
     printf("\n");
}

Cheers for figuring that out for me Ofcourse I needed a new line outside the loop! That helped alot!

Originally Posted by CommonTater

So... take the square brackets out and add a newline at the end of the formatting string in your printf() statement.

Look up printf() in your C Library Documentation, it will give you all the details on how printf() works.

And after I saw the first answer I realised this was exactly the problem.

Ofcourse I needed a newline after the loop!

Originally Posted by AndrewHunter

Additionally, void main is wrong. Read How to define main-FAQ

Just noticed it with void main(), realised it should be int main() instead.

Cheers for the help!