2.13.1.17 quantiles

1 Brief Information
2 Command Line Usage
3 X-Function Execution Options
4 Variables
5 Description
6 Examples
- 6.1 Example 1
- 6.2 Example 2
7 Algorithm
8 References
9 Related X-Functions

Brief Information

Compute quantiles on worksheet columns

Command Line Usage

1. quantiles ix:=Col(1);

2. quantiles ix:=Col(1) median:=mymedian;

X-Function Execution Options

Please refer to the page for additional option switches when accessing the x-function from script

Variables

Display Name	Variable Name	I/O and Type	Default Value	Description
Input	ix	Input vector	<active>	This variable specifies the range of input data for which quantiles will be calculated.
Minimum	min	Output double	<unassigned>	This variable specifies the output for the minimum value of the data set.
Q1	q1	Output double	<unassigned>	This variable specifies the output for the 1st quartile, that is, the value in a dataset that demarcates the lowest 25% of the values in an ordered set.
Median	median	Output double	<unassigned>	This variable specifies the output for the median or 2nd quartile, that is, the value in a dataset that demarcates the lowest 50% of the values in an ordered set.
Q3	q3	Output double	<unassigned>	This variable specifies the output for the 3rd quartile, that is, the value in a dataset that demarcates the lowest 75% of the values in an ordered set.
Maximum	max	Output double	<unassigned>	This variable specifies the output for the maximum value.
Interquartile Range	iqr	Output double	<unassigned>	This variable specifies the output for the interquartile range (IQR), that is, Q3 -Q1.
Index of Minimum	i1	Output double	<unassigned>	This variable specifies the output for the row index of the minimum value in the dataset.
Index of Maximum	i2	Output double	<unassigned>	This variable specifies the output for the row index of the maximum value in the dataset.

Description

quantiles are values from the data below which lie a given proportion of the data points in a given set. For example, 25% of data points in any set of data lay below the first quartile, and 50% of data points in a set lay below the second quartile, or median. When data is divided into 100 parts, percentiles can be calculated.

This analysis can give the basic information of the data, such as the minimum, maximum, 1^st quartile, median, 3^rd quartile and the interquartile range.

Examples

Example 1

Highlight the 1^st column of the active dataset
Right click the mouse and select fill column with: normal random numbers.
Type
```
quantiles
```
in the command window. Press Enter.
Then you can run
```
quantiles.=
```
to get the basic information about the data you specified, such as minimum, maximum, 1^st quantile, median, 3^rd quantile and interquantile range.

Example 2

The following script will get the minimum and maximum values and the corresponding row indices.

win -t wks;
string fn$=system.path.program$ + "Samples\graphing\group.dat"; 
impasc fname:=fn$; 
quantiles ix:=Col(1) max:=mymax min:=mymin i1:=a1 i2:=a2;
mymax=;
mymin=;
a1=;
a2=;