FT_DATATYPE_FREQ
Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help ft_datatype_freq”.
FT_DATATYPE_FREQ describes the FieldTrip MATLAB structure for freq data The freq data structure represents frequency or time-frequency decomposed channel-level data. This data structure is usually generated with the FT_FREQANALYSIS function. An example of a freq data structure containing the powerspectrum for 306 channels and 120 frequencies is dimord: 'chan_freq' defines how the numeric data should be interpreted powspctrm: [306x120 double] the power spectum label: {306x1 cell} the channel labels freq: [1x120 double] the frequencies expressed in Hz cfg: [1x1 struct] the configuration used by the function that generated this data structure An example of a freq data structure containing the time-frequency resolved spectral estimates of power (i.e. TFR) for 306 channels, 120 frequencies and 60 timepoints is dimord: 'chan_freq_time' defines how the numeric data should be interpreted powspctrm: [306x120x60 double] the power spectum label: {306x1 cell} the channel labels freq: [1x120 double] the frequencies, expressed in Hz time: [1x60 double] the time, expressed in seconds cfg: [1x1 struct] the configuration used by the function that generated this data structure Required fields: - label, dimord, freq Optional fields: - powspctrm, fouriesspctrm, csdspctrm, cohspctrm, time, labelcmb, grad, elec, cumsumcnt, cumtapcnt, trialinfo Deprecated fields: - <none> Obsoleted fields: - <none> Revision history: (2011/latest) The description of the sensors has changed, see FT_DATATYPE_SENS for further information. (2008) The presence of labelcmb in case of crsspctrm became optional, from now on the crsspctrm can also be represented as Nchan * Nchan. (2006) The fourierspctrm field was added as alternative to powspctrm and crsspctrm. The fields foi and toi were renamed to freq and time. (2003v2) The fields sgn and sgncmb were renamed into label and labelcmb. (2003v1) The initial version was defined. See also FT_DATATYPE, FT_DATATYPE_COMP, FT_DATATYPE_DIP, FT_DATATYPE_FREQ, FT_DATATYPE_MVAR, FT_DATATYPE_RAW, FT_DATATYPE_SOURCE, FT_DATATYPE_SPIKE, FT_DATATYPE_TIMELOCK, FT_DATATYPE_VOLUME