stanfordnlp/CoreNLP · error · IllegalArgumentException

conditionalLogProbGivenPrevious requires given one less…

Error message

conditionalLogProbGivenPrevious requires given one less than clique size ( ) but was

What it means

FactorTable models a clique of `windowSize` labels. conditionalLogProbGivenPrevious computes the log probability of the last label given the previous `windowSize-1` labels, and it validates that the `given` array is exactly windowSize-1 long before indexing. Passing any other length means the caller has built the conditioning context for the wrong clique size.

Solutions

Build `given` with exactly windowSize-1 labels: new int[table.windowSize()-1].
If the code supports multiple window sizes, derive the length from the FactorTable (windowSize) instead of hardcoding.
If you have the full clique, drop the last (or the position you're predicting) element before calling.

Example fix

// before
int[] given = {0, 1, 2}; // 3 labels for a window of 3
ft.conditionalLogProbGivenPrevious(given, 4);

// after
int[] given = {1, 2}; // windowSize-1 = 2 labels
ft.conditionalLogProbGivenPrevious(given, 4);

Defensive patterns

Strategy: validation

Validate before calling

// Java: check before calling
if (given.length != ft.windowSize - 1)
  throw new IllegalArgumentException("need " + (ft.windowSize-1) + " labels, got " + given.length);
double lp = ft.conditionalLogProbGivenPrevious(given, of);

Try / catch

// Java
try {
  double lp = ft.conditionalLogProbGivenPrevious(given, of);
} catch (IllegalArgumentException e) {
  // rebuild context with windowSize-1 labels and retry
  int[] fixed = Arrays.copyOf(given, ft.windowSize - 1);
  double lp = ft.conditionalLogProbGivenPrevious(fixed, of);
}

Prevention

Always derive context length from the FactorTable's windowSize, never hardcode.
Slice label histories with Arrays.copyOfRange(seq, pos-(windowSize-1), pos).
Write a helper method that builds clique contexts for all FactorTable queries.

When it happens

Trigger: Calling conditionalLogProbGivenPrevious(int[] given, int of) with given.length != windowSize-1 — e.g. passing a full clique of labels, an empty array, or a context built for a different window size.

Common situations: Copy-pasting example code written for a different CRF window size (e.g. order-1 vs order-2 CRFs); constructing the `given` array manually with off-by-one length; calling it in unit tests or `main` with hardcoded label arrays.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

AI-assisted analysis of stanfordnlp/CoreNLP@1b7edd19c4 (2026-09-10). Data as JSON: /api/errors/4e4c94781d44809c. Report an issue: GitHub.

Appendix: source

Thrown at src/edu/stanford/nlp/ie/crf/FactorTable.java:242

  public double logProb(int[] label) {
    return unnormalizedLogProb(label) - totalMass();
  }

  public double prob(int[] label) {
    return Math.exp(unnormalizedLogProb(label) - totalMass());
  }

  /**
   * Computes the probability of the tag OF being at the end of the table given
   * that the previous tag sequence in table is GIVEN. given is at the beginning,
   * of is at the end.
   *
   * @return the probability of the tag OF being at the end of the table
   */
  public double conditionalLogProbGivenPrevious(int[] given, int of) {
    if (given.length != windowSize - 1) {
      throw new IllegalArgumentException("conditionalLogProbGivenPrevious requires given one less than clique size (" +
              windowSize + ") but was " + Arrays.toString(given));
    }
    // Note: other similar methods could be optimized like this one, but this is the one the CRF uses....
    /*
    int startIndex = indicesFront(given);
    int numCellsToSum = SloppyMath.intPow(numClasses, windowSize - given.length);
    double z = ArrayMath.logSum(table, startIndex, startIndex + numCellsToSum);
    int i = indexOf(given, of);
    System.err.printf("startIndex is %d, numCellsToSum is %d, i is %d (of is %d)%n", startIndex, numCellsToSum, i, of);
    */
    int startIndex = indicesFront(given);
    double z = ArrayMath.logSum(table, startIndex, startIndex + numClasses);
    int i = startIndex + of;
    // System.err.printf("startIndex is %d, numCellsToSum is %d, i is %d (of is %d)%n", startIndex, numClasses, i, of);

    return table[i] - z;
  }

View on GitHub (pinned to 1b7edd19c4)