softmax static method
Implementation
static List<Value> softmax(List<Value> inputs) {
double maxVal = inputs.map((n) => n.data).reduce(math.max);
List<Value> expVals =
inputs.map((n) => (n - Value(maxVal, {n}, "softmax")).exp()).toList();
Value sumExp = expVals.reduce((a, b) => a + b);
List<Value> softmaxOut = expVals.map((n) => n / sumExp).toList();
return softmaxOut;
}