(A statistic is a number that summarizes some property of a set of data.) Common statistics include the mean (also known as the average) and the standard deviation (which tells how spread out the data are from the mean). (' Standard Deviation: 'Įxercise 5.2: A common programming task is computing statistics of a set of numbers. StatCalc calc // Computes stats for numbers entered by user.ĭouble item // One number entered by the user. * Computes and display several statistics for a set of non-zero * The return value will be -infinity if no numbers have been entered. * Return the largest item that has been entered. * The return value will be infinity if no numbers have been entered. * Return the smallest item that has been entered. Return Math.sqrt( squareSum/count - mean*mean ) * Return the standard deviation of all the items that have been entered. * The return value is Double.NaN if no numbers have been entered. * Return the average of all the items that have been entered. * Return the sum of all the numbers that have been entered.

* Return the number of items that have been entered into the dataset. * the numbers that have been added to the dataset using this method. Private double min = Double.POSITIVE_INFINITY // Smallest item seen. Private double max = Double.NEGATIVE_INFINITY // Largest item seen. Private double squareSum // The sum of the squares of all the items. Private double sum // The sum of all the items that have been entered. Private int count // Number of numbers that have been entered. * of items, the sum of the items, the average, the standard deviation, * statistics for the set of numbers that have been entered: The number Methods are provided to return the following Numbers are entered into the dataset using * An object of class StatCalc can be used to compute several simple statistics Changes from the original are shown in bold.

Statcalc java