Hello guys how do i square all the numbers in an arrayList?
i want to square each number with itself, is this possible?
https://processing.org/reference/sq_.html
please show your code with the loop over the arrayList
Welcome to the forum!
Yes, you for loop over the arraylist and use get and set command - see the reference for Arraylist
Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/util/function/UnaryOperator.html
// https://Discourse.Processing.org/t/square-an-arraylist-new-to-coding/15489/4
// GoToLoop (2019/Nov/14)
import java.util.List;
import java.util.function.UnaryOperator;
static final UnaryOperator<Float> SQ_FLOAT = new UnaryOperator<Float>() {
@Override final Float apply(final Float n) {
return sq(n);
}
};
static final List<Float> sqList(final List<Float> list) {
list.replaceAll(SQ_FLOAT);
return list;
}
final List<Float> floats = new ArrayList<Float>();
void setup() {
floats.add(PI);
floats.add(TAU);
floats.add(EPSILON);
println(floats); // [3.1415927, 6.2831855, 1.0E-4]
println(sqList(floats)); // [9.869605, 39.47842, 9.999999E-9]
exit();
}
Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/util/List.html#listIterator()
Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/util/ListIterator.html#set(E)
// https://Discourse.Processing.org/t/square-an-arraylist-new-to-coding/15489/5
// GoToLoop (2019/Nov/14)
import java.util.List;
import java.util.ListIterator;
static final List<Float> sqList(final List<Float> list) {
for (final ListIterator<Float> iter = list.listIterator(); iter.hasNext(); )
iter.set(sq(iter.next()));
return list;
}
final List<Float> floats = new ArrayList<Float>();
void setup() {
floats.add(PI);
floats.add(TAU);
floats.add(EPSILON);
println(floats); // [3.1415927, 6.2831855, 1.0E-4]
println(sqList(floats)); // [9.869605, 39.47842, 9.999999E-9]
exit();
}
Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/util/List.html#set(int,E)
// https://Discourse.Processing.org/t/square-an-arraylist-new-to-coding/15489/6
// GoToLoop (2019/Nov/14)
import java.util.List;
static final List<Float> sqList(final List<Float> list) {
for (int i = 0, len = list.size(); i < len; ++i) list.set(i, sq(list.get(i)));
return list;
}
final List<Float> floats = new ArrayList<Float>();
void setup() {
floats.add(PI);
floats.add(TAU);
floats.add(EPSILON);
println(floats); // [3.1415927, 6.2831855, 1.0E-4]
println(sqList(floats)); // [9.869605, 39.47842, 9.999999E-9]
exit();
}
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