Load Several/Multiple EPR Data/Spectra Files Simultaneously

Loads the EPR spectra from several/multiple text files (including the instrumental parameters in .DSC/.dsc or .par format) at once. Finally, the data are transformed either into a list of data frames or into a tidy/long table format. According to experimental quantity (e.g. temperature, microwave power, recording time...etc), names and var2nd.series (in the case of tidy = TRUE) arguments have to be specified.

Usage

readEPR_Exp_Specs_multif(
  name.pattern,
  dir_ASC,
  dir_dsc_par,
  col.names = c("index", "B_G", "dIepr_over_dB"),
  x.id = 2,
  x.unit = "G",
  Intensity.id = 3,
  convertB.unit = TRUE,
  qValues = NULL,
  norm.list.add = NULL,
  names,
  tidy = FALSE,
  var2nd.series = NULL,
  var2nd.series.factor = FALSE,
  origin = "xenon",
  ...
)

Arguments

name.pattern

Character string ('specimen'), inherited from list.files. A pattern from file name which might not necessarily appear at the beginning of the file name. One might also consult how to use regular expressions in R. THE SAME NAME AND name.pattern MUST BE USED FOR ALL FILE NAMES WITHIN THE SERIES.

dir_ASC

Path (defined by file.path or by character string) to directory where the ASCII files are stored.

dir_dsc_par

Path (defined by file.path or by character string) to directory where the .DSC/.dsc or .par files,including instrumental parameters, are stored.

col.names

Character string vector, inherited from fread, corresponding to column/variable names for individual file (see also readEPR_Exp_Specs). A safe rule of thumb is to use column names including the physical quantity notation with its units, Quantity_Unit like "B_G", "RF_MHz", "Bsim_mT" (e.g. pointing to simulated EPR spectrum \(x\)-axis)...etc, default: col.names = c("index","B_G",dIepr_over_dB) referring to column names coming from Xenon software.

x.id

Numeric index related to col.names vector pointing to independent variable, which corresponds to \(x\)-axis in the spectra or other plots. Default: x.id = 2 (for Xenon).

x.unit

Character string pointing to unit of quantity (coming from the original ASCII data, see also col.names argument) which is to be presented on \(x\)-axis of the EPR spectrum. Units like "G" ("Gauss"), "mT" ("millitesla"), "MHz" ("megahertz" in case of ENDOR spectra) or "Unitless" in case of \(g\)-values can be used. Default: x.unit = "G".

Intensity.id

Numeric index related to col.names vector, pointing to general intensity, like derivative intensity (dIepr_over_dB), integral one (e.g. single_Integ), double or sigmoid integral (e.g. Area)...etc. This corresponds to column/vector which should be presented like \(y\)-axis in the EPR spectra or other plots. Default: Intensity.id = 3 (for Xenon).

convertB.unit

Logical (default: convertB.unit = TRUE), whether upon reading, an automatic conversion between G and mT should be performed. If default is chosen, a new column/variable \(B\) in mT/G is created.

qValues

Numeric vector of Q-values (sensitivity factors to normalize EPR intensities) either loaded from instrumental parameters (.DSC or .par), therefore qValues = NULL (default), or in case of the origin = "winepr", they have to be provided by the spectrometer operator.

norm.list.add

Numeric list of vectors. Additional normalization constants in the form of vectors involving all (i.e. in addition to qValue) normalization(s) like e.g. concentration, powder sample weight, number of scans, ...etc (e.g. norm.list.add = list(c(2000,0.5,2),c(1500,1,3))). Default: norm.list.add = NULL.

names

Character string vector, corresponding either to values of additional quantity (e.g. temperature,microwave power...etc, c("240","250","260","270")) or to general sample coding by alpha character (e.g. c("a","b","c","d")) being varied by the individual experiments.

tidy

Logical, whether to transform the list of data frames into the long table (tidy) format, default: tidy = FALSE.

var2nd.series

Character string, if tidy = TRUE (see also the tidy argument) it is referred to name of the variable/quantity (such as "time","Temperature","Electrochemical Potential", "Microwave Power"...etc) altered during individual experiments as a second variable series (var2nd.series) and related to the spectral data.

var2nd.series.factor

Logical, whether to factorize var2nd.series column vector which is useful for plotting the spectra in overlay form. Default: var2nd.series.factor = FALSE, which is the case to visualize EPR spectra by plot-functions.

origin

Character string, corresponding to origin of the ASCII data, like from the most common spectrometers (from which the data are loaded automatically using the default parameters). Options are summarized in the following table (any other specific origin may be added later) =>

String	Description
"xenon"	default automatically loads data from the "Xenon" software with the default parameters.
"winepr"	automatically loads data from the "WinEpr" software.
"magnettech"	automatically loads data from the new "Magnettech" software (ESR5000 [11-0422]).
"other" (arbitrary string, e.g. "csv")	general, loads any other original data like `csv`, `txt`, `asc` incl. also data from other instrumental/spectrometer software. In such case, all the arguments for `readEPR_Exp_Specs` have to be set up accordingly.

...

additional arguments specified, see alsoreadEPR_Exp_Specs and fread.

Value

List of Data Frames (or long table tidy format) corresponding to multiple spectral data files/data sets. g-Value column (if x.unit = "mT" or "G") is automatically calculated during the processing and it is included in the data frame list/database as well.

Examples

if (FALSE) { # \dontrun{
## multiple ENDOR spectra at different temperatures recorded by `Xenon` software
## read and transformed into `longtable`, ready to plot the overlay
## EPR spectra => `var2nd.series.factor = FALSE` (default).
readEPR_Exp_Specs_multif(name.pattern = "^.*_sample_VT_",
                         file.path(".","ASCII_data_dir"),
                         file.path(".","DSC_data_dir"),
                         col.names = c("index",
                                       "RF_MHz",
                                       "Intensity"),
                         x.id = 2,
                         x.unit = "MHz",
                         Intensity.id = 3,
                         names = c("210","220","230","240"),
                         tidy = TRUE,
                         var2nd.series = "Temperature_K")
#
## multiple EPR spectra recorded at different temperatures
## by `WinEPR` software, experiments performed with a powder
## sample (m = 10 mg) and each spectrum acquired
## as 7 accumulations, the resulting database
## corresponds to list of data frames
readEPR_Exp_Specs_multif("^Sample_VT_",
                         file.path(".","ASCII_data_dir"),
                         file.path(".","DSC_data_dir"),
                         col.names = c("B_G","dIepr_over_dB"),
                         x.id = 1,
                         x.unit = "G",
                         Intensity.id = 2,
                         names = c("210","220","230","240"),
                         qValues = c(3400,3501,3600,2800),
                         norm.list.add = rep(list(c(10,7)),times = 4),
                         origin = "winepr")
#
## multiple `Xenon` EPR spectra related to one powder sample (m = 8 mg)
## where several instrumental parameters are changed
## at once, the file names (files are stored in the actual directory)
## start with the "R5228_AV_powder_", function returns all spectral data
## in `tidy` (long) table format
readEPR_Exp_Specs_multif(name.pattern = "R5228_AV_powder_",
                         dir_ASC = ".",
                         dir_dsc_par = ".",
                         names = c("a","b","c","d"),
                         tidy = TRUE,
                         var2nd.series = "sample",
                         norm.list.add = rep(list(8),4))
} # }

Usage

Arguments

Value

See also

Examples