show_constant {gmoTree}

Show constant columns

Description

Show all columns with no variation in their values for each data frame in the oTree list of data frames (except the ones in the info list). This function is helpful before running an experiment to check if there are unnecessary variables. You can check for columns that have any unchanging possible value or for columns containing only a specific value.

Usage

show_constant(oTree, value = "any")

Arguments

oTree

A list of data frames that were created by import_otree.

value

The value that is controlled to be the same within a column. If the value is set to "any", the function checks for columns where any possible values are identical.

Value

This function returns a list of vectors, one for each app, $all_apps_wide, the $Time and/or the $Chats data frame. Each vector contains the names of all variables with constant values. If there are no variables with constant values, the vector is empty.

Examples

# Use package-internal list of oTree data frames
oTree <- gmoTree::oTree

# Show all columns that contain only NAs
show_constant(oTree = oTree)
show_constant(oTree = oTree, value = NA)

# Show all columns that contain only -99
show_constant(oTree = oTree, value = -99)