finding non-zero minimum in array

This is a discussion on finding non-zero minimum in array within the C Programming forums, part of the General Programming Boards category; i have an array (d_available[i])with some zero elements and non zero elements i want to find the minimum of the ...

  1. #1
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    finding non-zero minimum in array

    i have an array (d_available[i])with some zero elements and non zero elements i want to find the minimum of the non zero elements (min_available)

    this is what i thought will work but still gives me 0 as minimium


    Code:
    min_available=d_available[0] ;
    for(i=0;i<NROWS;i++){
         if (min_available>d_available[i] && d_available> 0)
                    min_available=d_available[i];
     
                        }

  2. #2
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    Test for the minimum of zero elements available, and when you find one, add one tick onto an accumulator. Write some sort of a small "keep track" segment of code. Accumulators can use KeepTrack++ or KeepTrack = KeepTrack + 1
    Code:
    #include <stdio.h>
    
    int main ( void )
    {
    	int KeepTrack = 0;
    	int Counter = 0;
    	for ( Counter = 0; Counter < 10; Counter ++ )
    	{
    		printf("%d\n", KeepTrack);
    		KeepTrack++;
    	}
    	return 0;
    }
    If you provided more information..you'd have more repsonses/I'd help more.
    The world is waiting. I must leave you now.

  3. #3
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    well i dont need to know how many zerow i have i need to know what is the minimum value in my array which is not zero. ie if my array contains
    (0,1,2,5,8,9,10,0,2,0,0,1,2) my min will be 1 as i dont want to consider the zeros thats all what i want to do

    hope thats clear

  4. #4
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    If your first element (d_available[0]) is zero then your result will always be zero.

    Are negative values allowed?

  5. #5
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    One solution: initialise min_available with INT_MAX (assuming it is an int).

    min_available = INT_MAX; /* limits.h */

    Another solution (if negative numbers are not allowed ) is using 2 loops. The first loop to get the first non-zero number in the array and the second to check for smaller numbers (continue where the first loop ended).

  6. #6
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    negative values not allowed in the array and the element inside the array of arr all of type double

    could you please give me an example of how to use 2 loops one to get the first non-zero element and one to calculate the minimum

    thanx

  7. #7
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    Psuedo code to find first non 0 value
    Code:
    for tempindx = 0 while yourarray[tmpindx] != 0 tempindx++
    Psuedo code to find lowest value
    Code:
    for othertemp = tempindx while othertmp < NUMINDICES othertemp++
    if yourarray[othertemp] < yourarray[tempindx] && yourarray[othertemp] > 0
    tempindx = othertemp
    That should help a bit

  8. #8
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    here is the full code but still give me 0 as minimum??????

    Code:
    #include<stdio.h>
    #include<stdlib.h>
    #include<math.h>
    #define NROWS 20
    #define NCOLS 3 
    #define STATECOL 0
    #define XCOL 1
    #define YCOL 2             
    
    main()
    {
    FILE *inputdata;
    int i,j, xc,yc,tc,k;
    int taxi_list[NROWS][NCOLS];  
    int taxistates[NROWS],xtaxi[NROWS],ytaxi[NROWS];
    double d_available[NROWS],d_inuse[NROWS],d_oncall[NROWS];
    double min_available,min_inuse,min_oncall;
    double t_available,t_inuse,t_oncall;
    
    // customer info.
    
    printf(" please note that u need to press enter after entering any inputs \n Enter your location as X and Y coordenate:\n");
    printf("Enter your X-coordenate \n X=");
    scanf("%d",&xc);
    printf("Enter your Y-coordenate \n Y=");
    scanf("%d",&yc);
    printf("after how many mins you need the taxi ");
    scanf("%d",&tc);   
    
    //open input file to read
    inputdata=fopen("taxis_info.txt","r");
    if (inputdata==NULL){
    printf("error canot open taxis_info \n");
    exit(1);
    }   
    //read all info from input file to one array
      for (i=0;i<NROWS;i++){
            for(j=0;j<NCOLS;j++){
              fscanf(inputdata,"%d",&taxi_list[i][j]);
              }
            }
            
              
     //  creat 3 different arrays from the previous 20x3 array 
     //for taxistates,x-coord, y-coord of the taxis 
     
    for ( i = 0 ; i < NROWS ; i++ ) {
      taxistates[i] = taxi_list[i][STATECOL];
      xtaxi[i] = taxi_list[i][XCOL];
      ytaxi[i] = taxi_list[i][YCOL];
     } 
    //craet 3 arrays to hold distance from customer to available,inuse and oncall taxis
    //initialise the three arrays with zeros
    for(i=0;i<NROWS;i++){
         d_available[i]=0;
         d_inuse[i]=0 ;
         d_oncall[i]=0  ;
        
         }      
         
     //check taxistates f (ie available,inuse,oncall or not available taxis)
     //calculate distance between customer and  each available,inuse and oncall taxi 
     //place each set of distances in an array 
     
    for (i=0;i<NROWS;i++){
    if (taxistates[i]==1)
       d_available[i]=sqrt(pow(xc-xtaxi[i],2)+pow(yc-ytaxi[i],2));
    
    else if (taxistates[i]==2)
       d_inuse[i]=sqrt(pow(xc-xtaxi[i],2)+pow(yc-ytaxi[i],2)) ;
    
    else if (taxistates[i]==3)
       d_oncall[i]=sqrt(pow(xc-xtaxi[i],2)+pow(yc-ytaxi[i],2));
     
            }  
            
     
           
            
    // pick the smallest distance from d-available[i], d-inuse[i] and d-oncall[i]
    //divide the smallest distance by 20 to get t1 t2 t3
     
    for( i = 0; d_available[i] == 0 && i < NROWS; ++i ) ;
    if( i == NROWS ) {
      puts( "No nonzero at all" );
      /* error handling */
    }
    printf( "First nonzero element = d_available[%d]\n", i );
    for( min_available = 1; i < NROWS; ++i ) {
      if( d_available[i] != 0 )
        ++min_available;
    }
    printf( "min_available: %d\n", min_available );
    
                        
      
    
     
       
              }
    plz ayone can help

  9. #9
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    Code:
    #include <stdio.h>
    
    #define NROWS 8
    
    int main(void)
    {
       int i;
       int numbers[NROWS] = { 0, 0, 3, 7, 1, 0, 15, 1 };
       int min;
    
       for(i = 0; i < NROWS && numbers[i] == 0; i++); /* find first non-zero value in array */
    
       if(i == NROWS)
       {
          fprintf(stderr, "No non-zero values found\n");
          return -1;
       }
    
       min = numbers[i]; /* store first non-zero value */
    
       for( ; i < NROWS; i++)
          if(numbers[i] != 0 && numbers[i] < min)
             min = numbers[i];
    
       printf("min: %d\n", min);
    
       return 0;
    }

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