array being printed incorrectly

This is a discussion on array being printed incorrectly within the C Programming forums, part of the General Programming Boards category; Hi I'm new to this so be nice . I have written a function to print all the elements of ...

  1. #1
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    array being printed incorrectly

    Hi I'm new to this so be nice . I have written a function to print all the elements of an array. But currently it is printing the wrong values.

    here is part of my code:

    Code:
    void printarray(double *p,int l){
        unsigned short int i;
    
    
        for (i=0; i<l; i++)
        {
            printf("%d\n",*p);
            p++;
        }
    
    
    
    
    }
    
    int main()
    
    
    
    
    {
    
    
        double U,V,positions[6],distances[4],masses[2],F[4],*pdistances,*pF,*ppositions;
        const double G=6.673e-11;
    
        //inputs
        printf("what is the x -co-ordinate of p1 in m\n");
        scanf("%lf",positions[0]);
        printf("what is the y -co-ordinate of p1 in m\n");
        scanf("%lf",positions[1]);
        printf("what is the z -co-ordinate of p1 in m\n");
        scanf("%lf",positions[2]);
    
    
    
    
    
    
        printf("what is the x -co-ordinate of p2 in m\n");
        scanf("%lf",positions[3]);
        printf("what is the y -co-ordinate of p2 in m\n");
        scanf("%lf",positions[4]);
        printf("what is the z -co-ordinate of p2 in m\n");
        scanf("%lf",positions[5]);
       
        ppositions=positions;
        printarray(ppositions,6);
        
        return 0;
    
    }
    I hope you can help thanks.

  2. #2
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    First thing I noticed: if the array is double then the printf format statement needs to have the correct type for that. Not %d.

  3. #3
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    Yeah thanks, I've put in
    Code:
    printf("%lf\n",*p);
    and now it ouputs all zeros which is an improvement.

  4. #4
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    Then you have to supply the addresses to scanf instead of the values in the array.
    scanf("%lf",&positions[0]);

  5. #5
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    Oh yeah thanks, could I also write

    scanf("%f",positions);

    as position[0] is the same as *(positions+0)

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