List values of columns in the current H2O frame

Syntax

    _h2oframe _list [columnlist] [if] [in] [, options]

columnlist is a list of column names in the H2O frame; see Specifying a list of columns for more information.

 options                Description
 ---------------------------------------------------------------------------------
 abbreviate(#)          abbreviate column names to # display columns; default is
                        ab(8)
 string(#)              truncate string columns to # display columns
 noobs                  do not list observation numbers
 ---------------------------------------------------------------------------------

Description

_h2oframe _list displays the values of columns in the current H2O frame. If no columnlist is specified, the values of all the columns are displayed.

By default, only the first 10 observations are shown. This is intentional, because the data are fetched from the H2O cluster dynamically. Unlike Stata’s list command, which displays values from Stata’s dataset in memory, _h2oframe _list may not be efficient if the frame contains millions of observations. Having said that, you can use the if and in qualifiers to restrict the list to only the observations in which you are interested.

Options

abbreviate(#) allows you to specify the minimum abbreviation of column names to be considered. For example, you could specify abbreviate(16) if you never wanted columns abbreviated to less than 16 display columns. For most users, the number of display columns is equal to the number of characters. However, some languages, such as Chinese, Japanese, and Korean (CJK), require two display columns per character.

string(#) specifies that when string columns are listed, they be truncated to # display columns in the output. Any value that is truncated will be appended with “..” to indicate the truncation. string() is useful for displaying just a part of long strings.

noobs suppresses the listing of the observation numbers.

Examples

 Setup
     . sysuse auto
     . _h2oframe _put, into(auto)
     . _h2oframe _change auto

 List the first 10 observations of all columns
     . _h2oframe _list

 List the first 10 observations of the mpg and weight columns
     . _h2oframe _list mpg weight

 List the first 20 observations of the mpg and weight columns
     . _h2oframe _list mpg weight in 1/20

 List all the observations of the mpg and weight columns with values of mpg greater
 than 25
     . _h2oframe _list mpg weight if mpg > 25