/**
* What is the min/max/mean/stdev in the collection of aggregates (assuming its over numbers).
*
* <p>By default NaNs, Nulls and infinity are fully skipped. However, if the relevant parameters
* set to false they will be included in the "count" basis and thus influence the mean.
*
* <p>*
*/
public static <N extends Number> Stats<N> stats(
Aggregates<? extends N> aggregates,
boolean ignoreNulls,
boolean ignoreNaNs,
boolean ignoreInfinity) {
// For a single-test std. dev is based on:
// http://en.wikipedia.org/wiki/Standard_deviation#Rapid_calculation_methods
long count = 0;
long nullCount = 0;
long nanCount = 0;
long infCount = 0;
N min = null;
N max = null;
double sum = 0;
for (N n : aggregates) {
if (n == null) {
nullCount++;
continue;
}
double v = n.doubleValue();
if (Double.isNaN(v)) {
nanCount++;
continue;
}
if (Double.isInfinite(v)) {
infCount++;
continue;
}
if (min == null || min.doubleValue() > v) {
min = n;
}
if (max == null || max.doubleValue() < v) {
max = n;
}
sum += v;
count++;
}
final long fullCount =
count
+ (ignoreNulls ? 0 : nullCount)
+ (ignoreNaNs ? 0 : nanCount)
+ (ignoreInfinity ? 0 : infCount);
final double mean = sum / fullCount;
double acc = 0;
for (Number n : aggregates) {
if (n == null || Double.isNaN(n.doubleValue())) {
continue;
}
acc = Math.pow((n.doubleValue() - mean), 2);
}
double stdev = Math.sqrt(acc / fullCount);
return new Stats<>(min, max, mean, stdev, nullCount, nanCount);
}
/**
* @param bottom Lowest value to be included
* @param top Highest value to be included
* @param spacing How far apart should the contours be placed?
* @return List of the contour step values
*/
public static <N extends Number> List<N> steps(N bottom, N top, double spacing) {
int stepCount = (int) Math.ceil((top.doubleValue() - bottom.doubleValue()) / spacing);
ArrayList<N> steps = new ArrayList<>(stepCount);
for (int i = 0; i < stepCount; i++) {
steps.add(LocalUtils.addTo(bottom, (i * spacing)));
}
return steps;
}
private static <N extends Number> N scale(Class<N> type, double value, N min, N max) {
if (type.isAssignableFrom(Integer.class))
return type.cast(Integer.valueOf((int) (value * max.intValue() + min.intValue())));
if (type.isAssignableFrom(Double.class))
return type.cast((value * max.doubleValue() + min.doubleValue()));
if (type.isAssignableFrom(Long.class))
return type.cast(Long.valueOf((long) (value * max.longValue() + min.longValue())));
if (type.isAssignableFrom(Short.class))
return type.cast(Short.valueOf((short) (value * max.shortValue() + min.shortValue())));
if (type.isAssignableFrom(Byte.class))
return type.cast(Byte.valueOf((byte) (value * max.byteValue() + min.byteValue())));
if (type.isAssignableFrom(Float.class))
return type.cast(Float.valueOf((float) (value * max.floatValue() + min.floatValue())));
return null;
}
/**
* Returns the sum of all elements in this memory.
*
* @return the sum of all elements in this memory.
*/
public double getSum() {
double sum = 0d;
for (N value : list) {
sum += value.doubleValue();
}
return sum;
}
@Override
public Float64 apply(final N value) {
final double x = value.doubleValue();
Float64 result = Float64.ZERO;
if (x >= _min && x <= _max) {
result = Float64.valueOf(_k * x + _d);
}
return result;
}
@Override
public Float64 apply(final N value) {
final double x = value.doubleValue();
Float64 result = null;
if (x < _x1) {
result = Float64.ZERO;
} else if (x > _x2) {
result = Float64.ONE;
} else {
// result = Float64.valueOf(
// -((x*x - 2*x*_x2)*_y1 - (x*x - 2*x*_x1)*_y2)/
// (2*(_x2 - _x1))
// );
result = Float64.valueOf(_k * x * x / 2.0 + _d * x);
}
return result;
}
public <N extends Number> void setValue(N x) {
value = x.doubleValue();
}