void prepareInitialInput()

in Java/parkservices/src/main/java/com/amazon/randomcutforest/parkservices/preprocessor/ImputePreprocessor.java [91:153]
59 lines of code
23 McCabe index (conditional complexity)

    void prepareInitialInput() {
        boolean[][] missing = new boolean[initialValues.length][inputLength];
        for (int i = 0; i < initialValues.length; i++) {
            Arrays.fill(missing[i], false);
            int length = initialValues[i].length - inputLength;
            for (int j = 0; j < length; j++) {
                missing[i][(int) initialValues[i][inputLength + j]] = true;
            }
        }
        boolean[] startingValuesSet = new boolean[inputLength];

        if (imputationMethod == ZERO) {
            for (int i = 0; i < initialValues.length - 1; i++) {
                for (int j = 0; j < inputLength; j++) {
                    initialValues[i][j] = (missing[i][j]) ? initialValues[i][j] : 0;
                }
            }
        } else if (imputationMethod == FIXED_VALUES || defaultFill != null) {
            for (int i = 0; i < initialValues.length - 1; i++) {
                for (int j = 0; j < inputLength; j++) {
                    initialValues[i][j] = (missing[i][j]) ? initialValues[i][j] : defaultFill[j];
                }
            }
        } else { // no simple alternative other than linear interpolation
            for (int j = 0; j < inputLength; j++) {
                int next = 0;
                while (next < initialValues.length && missing[next][j]) {
                    ++next;
                }
                startingValuesSet[j] = (next < initialValues.length);
                if (startingValuesSet[j]) {
                    initialValues[0][j] = initialValues[next][j];
                    missing[0][j] = false;
                    // note if the first value si present then i==0
                    int start = 0;
                    while (start < initialValues.length - 1) {
                        int end = start + 1;
                        while (end < initialValues.length && missing[end][j]) {
                            ++end;
                        }
                        if (end < initialValues.length && end > start + 1) {
                            for (int y = start + 1; y < end; y++) { // linear interpolation
                                double factor = (1.0 * initialTimeStamps[start] - initialTimeStamps[y])
                                        / (initialTimeStamps[start] - initialTimeStamps[end]);
                                initialValues[y][j] = factor * initialValues[start][j]
                                        + (1 - factor) * initialValues[end][j];
                            }
                        }
                        start = end;
                    }
                } else {
                    // set 0; note there is no value in the entire column.
                    for (int y = 0; y < initialValues.length; y++) {
                        initialValues[y][j] = 0;
                    }
                }
            }
        }
        // truncate to input length, since the missing values were stored as well
        for (int i = 0; i < initialValues.length; i++) {
            initialValues[i] = Arrays.copyOf(initialValues[i], inputLength);
        }
    }