evaluateIntegralOn method

Complex evaluateIntegralOn(
  1. double lower,
  2. double upper
)

Evaluates the integral of the the polynomial between lower and upper.

Implementation

Complex evaluateIntegralOn(double lower, double upper) {
  var upperSum = const Complex.zero();
  var lowerSum = const Complex.zero();

  // The actual integration
  for (var n = coefficients.length - 1; n >= 0; --n) {
    final coeff = coefficient(n) ?? const Complex.zero();
    final denominator = Complex.fromReal(n + 1);

    upperSum += coeff * Complex.fromReal(upper).pow(n + 1) / denominator;
    lowerSum += coeff * Complex.fromReal(lower).pow(n + 1) / denominator;
  }

  return upperSum - lowerSum;
}