CODEWITHSUNDEEP
javaarraysloopsdoublemax
Maduri
Maduri

Reputation: 279

How to get maximum value from double data type value set?

I get the five double data type values from five different function.Without adding those value into array is there any efficient java code for get the maximum value from that five value set.

double d1=r1.function1();
double d2=r1.function2();
double d3=r1.function3();
double d4=r1.function4();
double d5=r1.function5();

double[] d=new  double[5];
for(int i=0:i<5;i++){
    d[i]="d"+i;
}
double x=max(d);

public static double max(double[] t) {
    double maximum = t[0];   // start with the first value
    for (int i=1; i<t.length; i++) {
        if (t[i] > maximum) {
            maximum = t[i];   // new maximum
        }
    }
    return maximum;
}

Without going this much effort is there any efficient way to get the maximum value from above double type data set? And also when adding value to the loop there also some error represent in d[i]="d"+i; part. Please provide me better solution.

Upvotes: 2

Views: 7003

Answers (8)

Rob Stoecklein
Rob Stoecklein

Reputation: 989

In Java 8:

Arrays.stream(darray).max().getAsDouble()

Full method (in our case, return zero if the array is empty; change your default as desired).

public static double max(final @Nullable double... values)
{
    return ((values != null) && (values.length > 0)) ? Arrays.stream(values).max().getAsDouble() : 0;
}

This method can be called with either an array or varargs parameter:

double[] darray = new double[]{43.7, 65.2, 99.1, 87.6};
double max1 = max(darray);
double max2 = max(1.2, 3.4, 5.6);

Upvotes: 2

elm
elm

Reputation: 20415

In Java 8, 

java.util.Arrays.parallelSort(d).get(d.size-1)

to get max value in (merge sorted) array.

Upvotes: 0

QBrute
QBrute

Reputation: 4535

You could use varargs instead of an array.

public double max(double... values) {
    int max = -Double.MAX_VALUE;
    for(double value : values) {
        if(value > max) {
            max = value;
        }
    }
    return max;
}

Then you call your method like double max = max(d1, d2, d3, d4, d5);

EDIT :

Your lines

for(int i=0:i<5;i++){
    d[i]="d"+i;
}

don't work, because "d"+i will create a String due to string concatentation and will not be the double variable with that name. You cannot fill your array like this. You will have to do:

d[0] = d1;
d[1] = d2;
d[2] = d3;
d[3] = d4;
d[4] = d5;

Upvotes: 1

Ritesh Bhakre
Ritesh Bhakre

Reputation: 203

List <Double> d = new ArrayList<>();
 d. add (d1);
d. add (d2);
d. add (d3);
d. add (d4);
d. add (d5);
Double max=Collections. max (d);

Upvotes: 0

Ruchira Gayan Ranaweera
Ruchira Gayan Ranaweera

Reputation: 35557

You can add d1,d2,d3,d4,d5 to TreeSet

Set<Double> set=new TreeSet<>(); // while you adding set will be sorted
// add values to set
List<Double> setAsList=new ArrayList(set); // convert set to list
System.out.println(setAsList.get(setAsList.size()-1)); // last value is the max

Upvotes: 0

nafas
nafas

Reputation: 5423

Collections.max(Arrays.asList(d));

if would be more efficient if instead of having d as an array. have it as list to begin with.

Upvotes: 1

kevdev
kevdev

Reputation: 1124

You dont have to put them in array yourself, let Java do that part of work using varargs:

public static double max(Double... numbers){
    double max = numbers[0];

    for(int i = 0; i < numbers.length; i++){
        if(numbers[i] > max){
            max = numbers[i];
        }
    }

    return max;
}

Upvotes: 0

Akash Thakare
Akash Thakare

Reputation: 22972

You can use ArrayList<Double> and than

    ArrayList<Double> alist=new ArrayList<Double>();
    //Add double values to this list

You can use Collections.max(alist) to get maximum value and Collections.min(alist) to get minimun value.

Upvotes: 4

Related Questions