import numpy as np def softmax(x: np.ndarray, axis=1) -> np.ndarray: """ Computes softmax array along the specified axis. """ e_x = np.exp(x) return e_x / e_x.sum(axis=axis, keepdims=True) def calibrate_sentiment_score( sentiment: float, thresh_neg: float, thresh_pos: float, zero: float = 0, ) -> float: if thresh_neg != (zero - 1) / 2: alpha_neg = -(3 * zero - 1 - 4 * thresh_neg) / (2 * zero - 2 - 4 * thresh_neg) / 2 if -1 < alpha_neg and alpha_neg < 0: raise ValueError(f"Incorrect value: {thresh_neg=} is too far from -0.5!") if thresh_pos != (zero + 1) / 2: alpha_pos = -(4 * thresh_pos - 1 - 3 * zero) / (2 + 2 * zero - 4 * thresh_pos) / 2 if 0 < alpha_pos and alpha_pos < 1: raise ValueError(f"Incorrect value: {thresh_pos=} is too far from 0.5!") if sentiment < 0: return (2 * zero - 2 - 4 * thresh_neg) * sentiment**2 + (3 * zero - 1 - 4 * thresh_neg) * sentiment + zero elif sentiment > 0: return (2 + 2 * zero - 4 * thresh_pos) * sentiment**2 + (4 * thresh_pos - 1 - 3 * zero) * sentiment + zero return zero def calibrate_sentiment( sentiments: np.ndarray[float], thresh_neg: float, thresh_pos: float, zero: float, ) -> np.ndarray[np.float64]: result = np.array( [ calibrate_sentiment_score(sentiment, thresh_neg=thresh_neg, thresh_pos=thresh_pos, zero=zero) for sentiment in sentiments ] ) return result.astype(np.float64) def scale_value(value, in_min, in_max, out_min, out_max): if in_min <= value <= in_max: scaled_value = (value - in_min) / (in_max - in_min) * (out_max - out_min) + out_min return scaled_value.round(3) else: raise ValueError(f"Input value must be in the range [{in_min}, {in_max}]") def get_sentiment( logits: np.ndarray, thresh_neg: float, thresh_pos: float, zero: float, ): probabilities = softmax(logits, axis=1) sentiments = np.matmul(probabilities, np.arange(5)) / 2 - 1 score = calibrate_sentiment( sentiments=sentiments, thresh_neg=thresh_neg, thresh_pos=thresh_pos, zero=zero, )[0] if score < -0.33: return scale_value(score, -1, -0.33, 0, 1), "NEGATIVE" elif score < 0.33: return scale_value(score, -0.33, 0.33, 0, 1), "NEUTRAL" else: return scale_value(score, 0.33, 1, 0, 1), "POSITIVE"