stanfordnlp/CoreNLP · error · IllegalArgumentException

conditionalLogProbGivenFirst requires of one less than…

Error message

conditionalLogProbGivenFirst requires of one less than clique size ( ) but was

What it means

conditionalLogProbGivenFirst computes the log probability of the label at the FIRST position given a following sequence `of`; it requires `of` to contain exactly windowSize-1 labels so that `of` plus the first label fills the whole clique. A differently sized `of` cannot be combined with the fixed first position, so it throws.

Solutions

Build `of` with exactly windowSize-1 labels (all clique positions except the first).
Read windowSize from the FactorTable rather than assuming an order.
If you meant to condition on a preceding context instead, use conditionalLogProbGivenPrevious, which validates `given` rather than `of`.

Example fix

// before (windowSize=3, needs 2)
ft.conditionalLogProbGivenFirst(0, new int[]{1});

// after
ft.conditionalLogProbGivenFirst(0, new int[]{1, 2});

Defensive patterns

Strategy: validation

Validate before calling

// Java
if (of.length != ft.windowSize - 1)
  throw new IllegalArgumentException("'of' must have " + (ft.windowSize-1) + " labels");
double lp = ft.conditionalLogProbGivenFirst(given, of);

Try / catch

// Java
try {
  lp = ft.conditionalLogProbGivenFirst(first, of);
} catch (IllegalArgumentException e) {
  System.err.println("Bad 'of' length " + of.length + " for window " + ft.windowSize);
  // rebuild `of` before retrying
}

Prevention

Remember the asymmetry: GivenFirst/GivenNext validate different args than GivenPrevious — check each method's contract.
Fill `of` with all clique positions except the first.
Derive sizes from ft.windowSize, not from the previous model's order.

When it happens

Trigger: Calling conditionalLogProbGivenFirst(int given, int[] of) where of.length != windowSize-1 — e.g. passing a single label where the table window is 3 (needs 2), or an array sized for a different window.

Common situations: Reusing query code written for order-1 CRFs on order-2+ tables; hardcoding `of` arrays in tests/demo main methods; confusing this method with the *GivenPrevious variants which validate the other argument.

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/7915bf7add06245b. Report an issue: GitHub.

Appendix: source

Thrown at src/edu/stanford/nlp/ie/crf/FactorTable.java:311

    }
    double[] result = new double[numClasses];
    for (int i = 0; i < numClasses; i++) {
      result[i] = table[indexOf(given, i)];
    }
    ArrayMath.logNormalize(result);
    return result;
  }

  /**
   * Computes the probability of the sequence OF being at the end of the table
   * given that the first tag in table is GIVEN. given is at the beginning, of is
   * at the end
   *
   * @return the probability of the sequence of being at the end of the table
   */
  public double conditionalLogProbGivenFirst(int given, int[] of) {
    if (of.length != windowSize - 1) {
      throw new IllegalArgumentException("conditionalLogProbGivenFirst requires of one less than clique size (" +
          windowSize + ") but was " + Arrays.toString(of));
    }
    // compute P(given, of)
    // double probAll = logProb(labels);
    double probAll = unnormalizedLogProb(given, of, windowSize - 1);

    // compute P(given)
    // double probGiven = logProbFront(given);
    double probGiven = unnormalizedLogProbFront(given);

    // compute P(given, of) / P(given)
    return probAll - probGiven;
  }

  /**
   * Computes the probability of the sequence OF being at the end of the table
   * given that the first tag in table is GIVEN. given is at the beginning, of is
   * at the end.

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