/**
* update with give grad and hess
*
* @param dtrain training data
* @param grad first order of gradient
* @param hess seconde order of gradient
* @throws XGBoostError native error
*/
public void boost(DMatrix dtrain, float[] grad, float[] hess) throws XGBoostError {
if (grad.length != hess.length) {
throw new AssertionError(
String.format("grad/hess length mismatch %s / %s", grad.length, hess.length));
}
JNIErrorHandle.checkCall(
XgboostJNI.XGBoosterBoostOneIter(handle, dtrain.getHandle(), grad, hess));
}
/**
* base function for Predict
*
* @param data data
* @param outPutMargin output margin
* @param treeLimit limit number of trees
* @param predLeaf prediction minimum to keep leafs
* @return predict results
*/
private synchronized float[][] pred(
DMatrix data, boolean outPutMargin, int treeLimit, boolean predLeaf) throws XGBoostError {
int optionMask = 0;
if (outPutMargin) {
optionMask = 1;
}
if (predLeaf) {
optionMask = 2;
}
float[][] rawPredicts = new float[1][];
JNIErrorHandle.checkCall(
XgboostJNI.XGBoosterPredict(handle, data.getHandle(), optionMask, treeLimit, rawPredicts));
int row = (int) data.rowNum();
int col = rawPredicts[0].length / row;
float[][] predicts = new float[row][col];
int r, c;
for (int i = 0; i < rawPredicts[0].length; i++) {
r = i / col;
c = i % col;
predicts[r][c] = rawPredicts[0][i];
}
return predicts;
}
/**
* Update (one iteration)
*
* @param dtrain training data
* @param iter current iteration number
* @throws XGBoostError native error
*/
public void update(DMatrix dtrain, int iter) throws XGBoostError {
JNIErrorHandle.checkCall(XgboostJNI.XGBoosterUpdateOneIter(handle, iter, dtrain.getHandle()));
}