public Row map()

in flink-ml-lib/src/main/java/org/apache/flink/ml/feature/hashingtf/HashingTF.java [118:158]
37 lines of code
7 McCabe index (conditional complexity)

        public Row map(Row row) throws Exception {
            Object inputObj = row.getField(inputCol);

            Iterable<Object> inputList;
            if (inputObj.getClass().isArray()) {
                inputList = Arrays.asList((Object[]) inputObj);
            } else if (inputObj instanceof Iterable) {
                inputList = (Iterable<Object>) inputObj;
            } else {
                throw new IllegalArgumentException(
                        "Input format "
                                + inputObj.getClass().getCanonicalName()
                                + " is not supported for input column "
                                + inputCol
                                + ". Supported options are Array and Iterable.");
            }

            Map<Integer, Integer> map = new HashMap<>();
            for (Object obj : inputList) {
                int hashValue = hash(obj);
                int index = nonNegativeMod(hashValue, numFeatures);
                if (map.containsKey(index)) {
                    if (!binary) {
                        map.put(index, map.get(index) + 1);
                    }
                } else {
                    map.put(index, 1);
                }
            }

            // Converts from map to a sparse vector.
            int[] indices = new int[map.size()];
            double[] values = new double[map.size()];
            int idx = 0;
            for (Map.Entry<Integer, Integer> entry : map.entrySet()) {
                indices[idx] = entry.getKey();
                values[idx] = entry.getValue();
                idx++;
            }
            return RowUtils.append(row, Vectors.sparse(numFeatures, indices, values));
        }