Statistic
A set of methods from Statistics and Probability Theory that allow for analysis of number sequences for statistical purposes. For example getting the average value or the most common value from an array.
Include
const Stat = require('total-serialism').Statistic;
const { sort, average } = require('total-serialism').Statistic;
Methods
sort
Sort an array in ascending or descending order. When strings are included they are sorted in alphabetical order with all numbers in the beginning.
arguments
- {Array} -> the array to sort
- {Int} -> postive/negative value for sorting direction (optional, default=1)
// Sort an array of numbers ascending
Stat.sort([-10, 8, 6, -12, -6, -7, 2, 4, 3, 11]);
//=> [ -12, -10, -7, -6, 2, 3, 4, 6, 8, 11 ]
// Sort an array of numbers descending with negative second argument
Stat.sort([-10, 8, 6, -12, -6, -7, 2, 4, 3, 11], -1);
//=> [ 11, 8, 6, 4, 3, 2, -6, -7, -10, -12 ]
// Sort a mixed array of strings and numbers
Stat.sort([10, 3.14, 'snare', 'kick', 5, -6, 'hat']);
//=> [ -6, 10, 3.14, 5, 'hat', 'kick', 'snare' ]
average
Get the average (the arithmetic mean) value from an array. This is one method of the three measures of central tendencies (Mean, Median, Mode).
Alias: mean()
arguments
- {Array} -> the array to take the average of
- {Bool} -> enable/disable the deep flag for n-dim arrays (default=true)
Stat.average([1, 2, 3, 4, 5, 6, 7, 8, 9]);
//=> 5
Stat.mean([2, -6, 2, 0, 10, 9, -2, 5, -8, -11, 1, -3]);
//=> -0.0833
center
Return the center value (the median) from an array. This is one method of the three measures of central tendencies (Mean, Median, Mode).
Alias: median()
arguments
- {Array} -> the array to get the median from
- {Bool} -> enable/disable the deep flag for n-dim arrays (default=true)
Stat.center([1, 5, 6, 9, 13]);
//=> 6
// Returns average of 2 middle values for even listlengths
// works with "official" statistics terminology
Stat.median([1, 7, 4, 2, 9, 5]);
//=> 4.5
common
Returns the most common value (the mode) from an array as an array. This is one method of the three measures of central tendencies (Mean, Median, Mode).
Alias: mode()
arguments
- {Array} -> the array to get the mode from
- {Bool} -> enable/disable the deep flag for n-dim arrays (default=true)
Stat.common([8, 4, 3, 11, 9, 0, 11, 2, 10, 5, 11, 0]);
//=> [ 11 ]
Stat.common([8, [4, 3], 9, [9, 0, [2, 10], 5], 11, 0, 11]);
//=> [ 11 ]
// In the case of a multi-modal system the array contains all common values
Stat.mode([8, 4, 3, 9, 9, 0, 2, 10, 5, 11, 0, 11]);
//=> [ 0, 9, 11 ]
minimum
Return the minimum value from an array (Also part of .Statistic)
Alias: min()
arguments
- {Array} -> the array to get the minimum from
Util.minimum([-38, -53, -6, 33, 88, 32, -8, 73]);
//=> -53
// Also works with n-dimensional arrays
Stat.min([-38, [-53, [-6, 33], 88, 32], [-8, 73]]);
//=> -53
maximum
Return the maximum value from an array (Also part of .Statistic)
Alias: max()
arguments
- {Array} -> the array to get the maximum from
Util.maximum([-38, -53, -6, 33, 88, 32, -8, 73]);
//=> 88
// Also works with n-dimensional arrays
Stat.max([-38, [-53, [-6, 33], 88, 32], [-8, 73]]);
//=> 88
change
Return the difference between consecutive numbers in an array. With an optional flag set to true as second argument the function also returns the difference between the first and last value in the array.
Alias: delta(), difference(), diff()
arguments
- {Array} -> the array to get the difference between each value from
- {Bool} -> returns diff between first and last (optional, default=false)
Util.change([0, 3, 7, 0, 12, 9, 5, 7]);
//=> [ 3, 4, -7, 12, -3, -4, 2 ]
// also returns difference between last and first value in array
Util.change([0, 3, 7, 0, 12, 9, 5, 7], true);
//=> [ 3, 4, -7, 12, -3, -4, 2, -7 ]
compare
Compare two arrays recursively and if all values of the array and subarrays are equal to eachother return a true boolean, else returns false.
arguments
- {Array} -> the first array to compare
- {Array} -> the second array to compare
// works with multidimensional arrays
Stat.compare([0, [3, [7, 5]], 12], [0, [3, [7, 5]], 12]);
//=> true
// works with strings as well
Stat.compare(['c', ['e', 'g']], ['c', ['e', 'g']]);
//=> true
// type has to match too
Stat.compare([0, 5, 7], [0, '5', 7]);
//=> false