variance
| 320 | |
| 321 | /// variance |
| 322 | double variance(const Vector& vector) { |
| 323 | double result = 0; |
| 324 | size_t N = vector.size(); |
| 325 | if (N > 0) { |
| 326 | double sumSquares = pow(boost::numeric::ublas::norm_2(vector), 2.0); |
| 327 | result = sumSquares / N - pow(mean(vector), 2); |
| 328 | } |
| 329 | return result; |
| 330 | } |
| 331 | |
| 332 | /// std dev |
| 333 | double stdDev(const Vector& vector) { |