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Select timerange

Source: R/data_selection.R
select_times.Rd

Generic function for selecting specific time ranges from a given dataset. Input can be a dataframe, or an object of class eeg_data, eeg_epochs, or eeg_evoked. Note this finds the closest times to those specified, so the time range returned may be slightly longer or shorter than that requested.

Usage

select_times(data, ...)

# Default S3 method
select_times(data, time_lim = NULL, ...)

# S3 method for class 'eeg_data'
select_times(data, time_lim = NULL, df_out = FALSE, ...)

# S3 method for class 'eeg_epochs'
select_times(data, time_lim, df_out = FALSE, ...)

# S3 method for class 'eeg_evoked'
select_times(data, time_lim, df_out = FALSE, ...)

# S3 method for class 'eeg_tfr'
select_times(data, time_lim = NULL, df_out = FALSE, ...)

Arguments

data

Data from which to select

...

Further arguments passed to or from other methods.

time_lim

A character vector of two numbers indicating the time range to be selected e.g. c(min, max), or a list to select specific times.

df_out

Returns a data frame rather than an object of the same type that was passed in.

Value

Data frame with only data from within the specified range.

eeg_data object

Methods (by class)

  • select_times(default): Default select times function

  • select_times(eeg_data): Select times from an eeg_data object

  • select_times(eeg_epochs): Select times in eeg_epochs objects

  • select_times(eeg_evoked): Select times in eeg_evoked objects

  • select_times(eeg_tfr): Select times from an eeg_tfr object

See also

select_elecs() and select_epochs()

Other Data selection functions: select_elecs()

Author

Matt Craddock, matt@mattcraddock.com

Examples

## Select timepoints from -.1 to .3
demo_epochs
#> Epoched EEG data
#> 
#> Number of channels	: 11 
#> Number of epochs	: 80 
#> Epoch limits		: -0.197 - 0.451 seconds
#> Electrode names		: A5 A13 A21 A29 A31 B5 B6 B8 B16 B18 B26 
#> Sampling rate		: 128  Hz
#> Reference		: average 
short_epochs <- select_times(demo_epochs, time_lim = c(-.1, .3))
short_epochs
#> Epoched EEG data
#> 
#> Number of channels	: 11 
#> Number of epochs	: 80 
#> Epoch limits		: -0.096 - 0.295 seconds
#> Electrode names		: A5 A13 A21 A29 A31 B5 B6 B8 B16 B18 B26 
#> Sampling rate		: 128  Hz
#> Reference		: average 
short_epochs <- select_times(demo_epochs, time_lim = list(-.1, .15, .3))
#> Returning closest time points to those requested: -0.104 0.146 0.295 
head(short_epochs$timings)
#> # A tibble: 6 × 3
#>   epoch sample   time
#>   <dbl>  <dbl>  <dbl>
#> 1     1   4076 -0.104
#> 2     1   4204  0.146
#> 3     1   4280  0.295
#> 4     2   6985 -0.104
#> 5     2   7113  0.146
#> 6     2   7189  0.295