ncalm

/*
NGRAMS

Converts a text string to n-grams

Inputs:
	- text (string): the text string to convert
	- n (int): the number of elements to output in each n-gram
	- strict (bool): whether to output incomplete n-grams at the end of the array
	

ncalm

/*
ONEHOT

One-hot encodes a catagorical variable

Inputs
	- rng: a single-column array or range of categorical data (usually text)
	
Returns
	For each unique value v in rng, a new column with header rng.header & "_" & v

ncalm

/*
LEV

Calculates the Levenshtein distance between two strings

Inputs
	- a: a string to compare with b
	- b: a string to compare with a
	- [ii]: the [ii]th position in string a
	- [jj]: the [jj]th position in string b

ncalm

/*
RECURSIVEFILTER

Filters an array or range recursively using a list of columns and criteria to apply

Inputs
	- dat: 		the array or range of data to filter
	- cols: 	Either a one-dimensional horizontal array of column indices representing
				    columns in dat. e.g. {1,2} means "filter columns 1 and 2"
            OR

ncalm

/*
GROUPAGGREGATE

Creates summary tables of data similar to SQL's GROUP BY queries

Inputs
	- dat: 	a range or array of data with at least two columns, 
			one of which's control value must be "group" and one not "group"
	- control: a single-row array, where COLUMNS(control)=COLUMNS(dat), of values from this list:
		group - the values in this column will be output as row headers

ncalm

/*
DESCRIBE

Creates tables of statistics similar to the Analysis Toolpak Add-in "Summary statistics" feature.
Including support for text columns and additional statistics for numeric columns.

Inputs
	- data: a range or array of data with at least one column
	- has_header: TRUE if data includes a header row, FALSE otherwise
	

ncalm

/*
GROWTHFROMOFFSET

Calculates the growth that a current month represents when compared
to the same measure an arbitrary number of months ago

Inputs:
	- month_col: a Table column, a cell range (using absolute references) or an array containing the months formatted as dates
	- value_col : a Table column, a cell range (using absolute references) or an array containing the values
	- month_offset : the number of months prior to the month on the current row that you want to compare with

ncalm

/*
FORECAST.ETS.COMPARE

Creates an array enabling comparison of actuals vs forecasted data

Inputs:
  Required:
  - data - this is a two-column range or array of data where one of the columns contains dates and one of the columns contains the values to be used as the basis for the forecast
  - dates_in_column - is an integer, either 1 or 2, telling the function which of the two selected columns in data contains the dates
  - values_in_column - is an integer, either 1 or 2, telling the function which of the two selected columns in data contains the values to be used as the basis for the forecast

ncalm

/*
ISLEAPYEAR

Calculates whether a year is a leap year

Inputs:
  - yr is the year you want to test
  
Returns:
  TRUE if the year is a leap year, FALSE otherwise

ncalm

/*
OUTLIERS

These lambda functions allow us to quickly apply the standard deviation test to a series of transformed variables

Included in this file:

OUTLIER.THRESHOLDS - for calculating outlier thresholds using a standard deviation test

inputs: