--- title: "User Guide" subtitle: "Package 'photobiologyInOut' `r packageVersion('photobiologyInOut')` " author: "Pedro J. Aphalo" date: "`r Sys.Date()`" output: rmarkdown::html_vignette: toc: yes vignette: > %\VignetteIndexEntry{User Guide} %\VignetteEngine{knitr::rmarkdown} %\VignetteEncoding{UTF-8} --- ## Introduction Package 'photobiologyInOut' defines functions for importing spectral data from different instruments, data repositories and simulation models, and for data exchange with R packages 'hyperSpec', 'colorSpec' and 'pavo' by reading or writing objects of classes defined in them (see Tables at the start of each section). As of version 0.4.21 packages 'hyperSpec' and 'pavo' need to be installed only if the corresponding functions will be used. This avoids bloat when these functions are not needed. If the vignette is built or examples attempted to run in a system where these packages are not installed, some output will be missing but no error will be triggered. All functions that read data from files attempt to decode and store as metadata the information present in file headers. In addition, in most cases the unchanged header of the file is stored unaltered as a comment in the constructed objects. It should be remembered, though, that this package has been developed based on the _example files_ I had access to. Files from the same instruments with different hardware configurations, different firmware versions, or even settings may differ substantially. In many cases the output is produced by software in a host computer rather by the instrument itself, adding further uncertainties and possible differences due to for example the operating system of the host computer. A further complication is that in some cases the format of dates, times and numbers depends on the locale settings in use at the time of data acquisition, or analysis. For all those reasons, do expect to have to do some debugging, and most importantly always validate the imported data against the original file (remembering to run a new validation each time there is a software or firmware update) or update of this package as I test each version before release only with the example files I have available, which are not many. ## Preliminaries ```{r, setup, include=FALSE, cache=FALSE} library(knitr) # Are the packages used in examples installed? eval_chunks <- requireNamespace("ggspectra", quietly = TRUE) && requireNamespace("photobiologyWavebands", quietly = TRUE) # eval_colorSpec <- requireNamespace("colorSpec", quietly = TRUE) && eval_chunks eval_colorSpec <- eval_chunks eval_pavo <- requireNamespace("pavo", quietly = TRUE) && eval_chunks eval_hyperSpec <- requireNamespace("hyperSpec", quietly = TRUE) && eval_chunks opts_chunk$set(fig.align='center', fig.show='hold', fig.width=7, fig.height=6, size="footnotesize", eval=eval_chunks) options(replace.assign = TRUE, width = 55, warnPartialMatchAttr = FALSE, warnPartialMatchDollar = FALSE, warnPartialMatchArgs = FALSE) # setting TZ may be needed in some geographic locations as some Windows TZ # strings are not recognized by all versions of R Sys.setenv(TZ = 'UTC') ``` When loading suggested packages flags are set based on success and later used to selectively evaluate code chunks. ```{r, message=FALSE} library(photobiology) library(photobiologyWavebands) library(photobiologyInOut) library(lubridate) library(ggspectra) library(readr) library(colorSpec) if (eval_pavo) {library(pavo)} if (eval_hyperSpec) {library(hyperSpec)} ``` ```{r} # plot defaults theme_set(theme_bw()) # ggplot2 set_annotations_default(annotations = c("+", "title:what:when")) # decrease lines printed options(tibble.print_max = 5, tibble.print_min = 3, photobiology.strict.range = NA_integer_) ``` ## Spectrometer output files In the examples we use function _system-file_ to reliably locate the example files included in the package. For reproducing the examples with these files, this call is needed. When using user's files only the path as a character string needs to be passed as argument. In most cases the quantities in the files can be identified from the file contents allowing a single function to work adaptively. In cases when the format returned by different models of spectrometers from the same supplier is largely consistent, then a single function can read them all. In some cases the format depends on the computer software used to acquire the data, of which a single supplier may have had more than one over the years, thus requiring multiple functions. Some of the instruments supported have long been discontinued but in their time were very popular, like the LI-COR LI-1800 spectrometer from the late 1980's. The coverage of brands and models is limited by the instruments I have had access to, or have had at least access to a sample of files. As of version 0.4.24 data can be imported from files created by spectrometers and/or software from six different suppliers. Functions for importing measured spectral data. | R function | Instrument | Program | `class` of value | |:-----------------------|:-----------------------|:------------------|:-----------------| | `read_oo_ssirrad()` | Ocean Optics spectrom. | SpectraSuite | `source_spct` | | `read_oo_ssdata()` | Ocean Optics spectrom. | SpectraSuite | `raw_spct` | | `read_oo_jazirrad()` | Ocean Optics Jaz | *instrument* | `source_spct` | | `read_oo_jazpc()` | Ocean Optics Jaz | *instrument* | `filter_spct` | | `read_oo_jazpc()` | Ocean Optics Jaz | *instrument* | `reflector_spct` | | `read_oo_jazdata()` | Ocean Optics Jaz | *instrument* | `raw_spct` | | `read_oo_pidata()` | Ocean Optics spectrom. | STS DK (Raspbian) | `raw_spct` | | `read_wasatch_csv()` | Wasatch Phot. spectrom. | Enlighten | `raw_spct` | | `read_wasatch_csv()` | Wasatch Phot. spectrom. | Enlighten | `filter_spct` | | `read_wasatch_csv()` | Wasatch Phot. spectrom. | Enlighten | `reflector_spct` | | `read_wasatch_csv()` | Wasatch Phot. spectrom. | Enlighten | `source_spct` | | `read_cid_spectravue_csv()` | CID Bio-Science CI-710s | *instrument* | `filter_spct` | | `read_cid_spectravue_csv()` | CID Bio-Science CI-710s | *instrument* | `reflector_spct` | | `read_cid_spectravue_csv()` | CID Bio-Science CI-710s | *instrument* | `object_spct` | | `read_avaspec_csv()` | Avantes spectrom. | *instrument?* | `source_spct` | | `read_macam_file()` | Macam | *instrument* | `source_spct` | | `read_li180_txt()` | LI-COR LI-180 | *instrument* | `source_spct` | | `read_m_li180_txt()` | LI-COR LI-180 | *instrument* | `source_mspct` | | `read_licor_prn()` | LI-COR LI-1800 | PC1800 (MS-DOS) | `source_spct` | | `read_licor_prn()` | LI-COR LI-1800 | PC1800 (MS-DOS) | `filter_spct` | | `read_licor_prn()` | LI-COR LI-1800 | PC1800 (MS-DOS) | `reflector_spct` | | `read_m_licor_prn()` | LI-COR LI-1800 | PC1800 (MS-DOS) | `source_mspct` | | `read_m_licor_prn()` | LI-COR LI-1800 | PC1800 (MS-DOS) | `filter_mspct` | | `read_m_licor_prn()` | LI-COR LI-1800 | PC1800 (MS-DOS) | `reflector_mspct` | | `read_spectrapen_csv()` | PSI SpectraPen | *instrument* (?) | `source_spct` | ### Ocean Optics Jaz #### Raw detector counts Reading a raw data file generated by Ocean Optics' Jaz spectrometer. The light source was the Jaz PX pulsed Xenon light module. The first few lines of the file look like this, with W for wavelength, D for dark, R for reference, S for sample and P for processed (all spectral data values are raw detector counts): ``` Jaz Data File ++++++++++++++++++++++++++++++++++++ Date: Mon Apr 25 12:49:11 2016 User: jaz Dark Spectrum Present: Yes Reference Spectrum Present: Yes Processed Spectrum Present: Yes Spectrometers: JAZA3098 Integration Time (usec): 748000 (JAZA3098) Spectra Averaged: 1 (JAZA3098) Boxcar Smoothing: 0 (JAZA3098) Correct for Electrical Dark: No (JAZA3098) Strobe/Lamp Enabled: Yes (JAZA3098) Correct for Detector Non-linearity: No (JAZA3098) Correct for Stray Light: No (JAZA3098) Number of Pixels in Processed Spectrum: 2048 >>>>>Begin Processed Spectral Data<<<<< W D R S P 190.313904 0.000000 0.000000 0.000000 0.000000 190.695511 0.000000 0.000000 0.000000 0.000000 191.077087 1138.953125 1123.134277 1102.795898 228.570541 191.458633 1184.149658 1227.086426 1059.859131 -289.473419 191.840149 1175.110352 1193.188965 1132.173584 -237.500336 ... ``` ```{r} jaz.raw.file <- system.file("extdata", "spectrum.jaz", package = "photobiologyInOut", mustWork = TRUE) jazraw.spct <- read_oo_jazdata(file = jaz.raw.file) jazraw.spct <- trim_wl(jazraw.spct, range = c(250, 900)) ``` Plotting the spectrum. ```{r} autoplot(jazraw.spct) ``` The metadata stored in attributes can be accessed with functions. It is clear, that not all settings can be recovered from the file. However, we store the record will all the fields which would have been filled if the data had been acquired directly from R using package 'ooacquire'. ```{r} getWhenMeasured(jazraw.spct) ``` ```{r} getInstrDesc(jazraw.spct) ``` ```{r} getInstrSettings(jazraw.spct) ``` #### Spectral energy irradiance Reading an "Absolute Irradiance File" (sic) generated by Ocean Optics' Jaz spectrometer results in a `source_spct` object. In this example, the light source measured was a `white' fluorescent tube. The first few lines of the file look like this: ``` Jaz Absolute Irradiance File ++++++++++++++++++++++++++++++++++++ Date: Tue Feb 03 09:44:41 2015 User: jaz Dark Spectrum Present: Yes Processed Spectrum Present: Yes Spectrometers: JAZA1065 Integration Time (usec): 193000 (JAZA1065) Spectra Averaged: 3 (JAZA1065) Boxcar Smoothing: 5 (JAZA1065) Correct for Electrical Dark: Yes (JAZA1065) Strobe/Lamp Enabled: No (JAZA1065) Correct for Detector Non-linearity: Yes (JAZA1065) Correct for Stray Light: No (JAZA1065) Number of Pixels in Processed Spectrum: 2048 Fiber (micron): 3900 Collection Area: 0.119459 Int. Sphere: No >>>>>Begin Processed Spectral Data<<<<< W D S P 188.825226 0.000000 0.000000 0.000000 189.284851 0.000000 0.000000 0.000000 189.744415 -89.659378 -90.917900 -0.000000 190.203964 -106.165916 -96.419785 0.000000 ... ``` ```{r} jaz.s.irrad.file <- system.file("extdata", "spectrum.JazIrrad", package = "photobiologyInOut", mustWork = TRUE) jaz.spct <- read_oo_jazirrad(file = jaz.s.irrad.file) jaz0.spct <- jaz.spct jaz.spct <- trim_wl(jaz.spct, range = c(290, 800)) ``` Plotting the spectrum. ```{r} autoplot(jaz.spct) ``` ### Cleaning spectral data We can see that the data have problems. We get a warning because the data include negative values for spectral irradiance. We will use some methods from package 'photobiology' to correct the problem. As the data are noisy we cannot just shift the scale so that the most negative value becomes zero. Neither can we replace all negative values with zeros, as this would create bias. In the following code chunk we will use a region of the spectrum in which spectral irradiance is known to be equal to zero as reference to shift the scale zero. Afterwards we discard data ``known'' to be zero, and for which the instrument calibration is not valid, and finally we plot the spectrum. ```{r} jaz.spct <- fshift(jaz0.spct, range = c(255, 290), f = "mean") jaz.spct <- trim_wl(jaz.spct, range = c(290, 800)) autoplot(jaz.spct) ``` We can next try to smooth the spectrum as it is very noisy outside the visible region. ```{r} jaz.spct <- smooth_spct(jaz.spct) autoplot(jaz.spct) ``` Photon and energy irradiances. ```{r} e_irrad(jaz.spct, PAR()) # W m-2 ``` All in one statement. ```{r} autoplot(read_oo_jazirrad(file = jaz.s.irrad.file)) ``` As above but limiting the wavelength range plotted. ```{r} autoplot(read_oo_jazirrad(file = jaz.s.irrad.file), range = c(250,850)) ``` Adding our custom ``adaptive'' smoothing. ```{r} autoplot(smooth_spct(read_oo_jazirrad(file = jaz.s.irrad.file)), range = c(250,850)) ``` ### Other modular spectrometers from Ocean Optics Now a file from an Ocean Optics' Q6500 spectrometer, with data processed with the Spectra Suite software. Format of the header is similar, but not identical. The first few lines of the file look like this: ``` SpectraSuite Data File ++++++++++++++++++++++++++++++++++++ Date: Mon May 06 15:13:40 CEST 2013 User: User Dark Spectrum Present: Yes Reference Spectrum Present: No Number of Sampled Component Spectra: 1 Spectrometers: QEB1523 Integration Time (usec): 100000 (QEB1523) Spectra Averaged: 1 (QEB1523) Boxcar Smoothing: 0 (QEB1523) Correct for Electrical Dark: No (QEB1523) Strobe/Lamp Enabled: No (QEB1523) Correct for Detector Non-linearity: No (QEB1523) Correct for Stray Light: Yes (QEB1523) Number of Pixels in Processed Spectrum: 1044 >>>>>Begin Processed Spectral Data<<<<< 199.08 0.0000E00 199.89 0.0000E00 200.70 0.0000E00 ... ``` ```{r} q.raw.file <- system.file("extdata", "spectrum.SSIrrad", package = "photobiologyInOut", mustWork = TRUE) autoplot(read_oo_ssirrad(file = q.raw.file)) ``` ### Array spectrometers from Wasatch Photonics Enlighten can save spectral data in a variety of file formats. The function `read_wasatch_csv()` reads CSV files with spectral data in columns. It is designed so that it can read any variation of this file format. In Enlighten it is possible to select which columns are included in the file so their number can vary. However, the header is rich in information and this allows in many but not all cases to guess based on the "Technique" used in Enlighten the type of data being imported. This means that in some cases the user needs to pass an argument to parameter `s.qty`. This is also the case when the column to be extracted is not that with heading "Processed" in the CSV file. The metadata is as for Ocean Insight/Ocean Optics spectrometers copied to attributes in the returned object. Format of the header is simple and rather easy to parse. The header of the file and the first few lines look like this: ``` ENLIGHTEN Version,2.2.7 Measurement ID,20211003-134004-612972-WP-00591 Serial Number,WP-00591 Model,WP-UV-VIS-C-S-25 Label,13:40:04 WP-00591 Declared Match, Declared Score,0 Scan Averaging,1 Boxcar,0 Technique,Scope Baseline Correction Algo, ROI Pixel Start,0 ROI Pixel End,1023 Slit Width,25 Vignetted,False Interpolated,False Raman Intensity Corrected,False Deconvolved,False Integration Time,60 Timestamp,2021-10-03 13:40:04.612972 Note,Dark substracted Temperature,-15.327480412352088 CCD C0,247.9385986328125 CCD C1,0.5131465792655945 CCD C2,-0.00012270470324438065 CCD C3,7.728250039917839e-08 CCD Offset,0 CCD Gain,1.9 Laser Wavelength,0.0 Laser Enable,False Laser Power,100 Laser Temperature,0 Pixel Count,1024 Pixel,Wavelength,Processed 0,247.94,175.00 1,248.45,178.00 ``` ```{r} file.name <- system.file("extdata", "enlighten-wasatch-scope.csv", package = "photobiologyInOut", mustWork = TRUE) wasatch.raw.spct <- read_wasatch_csv(file = file.name, extra.cols = "drop") ``` ```{r} summary(wasatch.raw.spct) ``` ```{r} autoplot(wasatch.raw.spct) ``` ### Modular spectrometers from Avantes Avantes' two column .csv files can also be imported. ```{r} ava.raw.file <- system.file("extdata", "spectrum-avaspec.csv", package = "photobiologyInOut", mustWork = TRUE) autoplot(read_avaspec_csv(file = ava.raw.file), range = c(280, 900), unit.out = "photon") ``` ### Scanning spectrometer from Macam Macam's single column DTA files can also be imported. The first few lines of the file look like this with all data in a single column with alternate rows for wavelengths (in nm) and irradiances, and a very terse header: ``` @19/5/1997 @17:44:58 #No Title 2.5000000000E+02 0.0000000000E+00 2.5100000000E+02 0.0000000000E+00 2.5200000000E+02 0.0000000000E+00 ... ``` ```{r} macam.raw.file <- system.file("extdata", "spectrum.DTA", package = "photobiologyInOut", mustWork = TRUE) autoplot(read_macam_dta(file = macam.raw.file)) ``` ### LI-180 array dector spectrometer from LI-COR The LI-COR LI-180 is a portable, self-contained instrument, with relatively low spectral resolution. This instrument measures spectral irradiance in the range 380 nm to 780 nm. There is only one hardware configuration but firmware updates have been released. This instrument can save the spectral data in different formats. The "XXX" format includes a rather long header, followed by spectral data, then followed by a file footer. The long header can contain various summaries computed from the spectrum, as well as date and time, and information on the instrument. The top of the file we will read looks like this: ``` Model Name LI-180 Serial Number A18M0157 Time 2021/03/02_09:24:26 PPFD 129.879440 PFD 171.178452 PFD-UV 2.336031 PFD-B 33.417435 PFD-G 46.992531 PFD-R 49.469433 PFD-FR 38.963074 Custom1(655~665nm) 5.057602 Custom2(725~735nm) 4.957998 Custom3(650~670nm) 10.137251 Custom4(720~740nm) 9.965228 UV% 1.364676 B% 19.521980 G% 27.452354 R% 28.899324 FR% 22.761662 Custom1% 2.954579 Custom2% 2.896391 Custom3% 5.922037 Custom4% 5.821544 R:B 1.480348 R:FR 1.269649 R:G 1.052708 B:G 0.711122 UV:B 0.069905 UV:FR 0.059955 B:G:R 0.000000 B:R:FR 0.000000 UV:B:G:R:FR 0.000000 Ratio1(Custom1:Custom2) 1.020090 Ratio2(Custom3:Custom4) 1.017262 Ratio3 0.000000 Ratio4 0.000000 LambdaP 495.000000 LambdaPV 106.211479 LambdaD 554.000000 LUX 7366.741699 IRR 35.163498 fc 684.641418 I-Time 92.000000 380nm 27.503876 381nm 27.968113 382nm 28.452974 383nm 28.665405 ... ``` And the footer containing chromaticity data: ``` ... 778nm 82.020149 779nm 82.078781 780nm 82.042412 CCT 5465.000000 Duv 0.004667 x 0.333318 y 0.351069 u' 0.203671 v' 0.482666 deltax 0.000063 deltay 0.009303 deltau' -0.003491 deltav' 0.004648 Purity 5.337072 CRI 98.779282 R1 98.665459 R2 99.470703 R3 98.974945 R4 98.248100 R5 98.830368 R6 99.473335 R7 98.902351 R8 97.668961 R9 94.101921 R10 99.232346 R11 98.246521 R12 99.336227 R13 98.899147 R14 99.324699 R15 97.831963 ``` Function `read_licor_espd()` will automatically extract the spectral data, date and time, and serial number. ```{r} licor_espd.file <- system.file("extdata", "LI-180-irradiance.txt", package = "photobiologyInOut", mustWork = TRUE) li180.spct <- read_li180_txt(file = licor_espd.file) ``` In all cases as much information as possible is decoded, and the data file headers are preserved as comments in the source.spct objects. ```{r} li180.spct cat(comment(li180.spct)) getInstrDesc(li180.spct) getInstrSettings(li180.spct) autoplot(li180.spct, unit.out = "photon") ``` ### LI-1800 scanning spectrometer from LI-COR The LI-COR LI-1800 was developed in the early 1980's and remained available for many years. Some units are still in use although the technology has been superceeded. If re-calibrated these instruments are still useful. Spectral photon irradiance output files generated by LI-COR's PC1800 program for the LI-1800 spectroradiometer. These files have a relatively detailed header, but it lacks year information. Files can contain either energy or photon based spectral irradiances, and this is signalled in the header. In this example photon (= quantum) spectral irradiance is returned. The first few lines of the file look like this: ``` "FILE:FL2" "REM: TLD 36W/865 (QNTM)" "LIMS: 300- 900NM" "INT: 1NM" "DATE:08/23 16:32" "MIN: 300NM 1.518E-04" "MAX: 546NM 7.491E-01" 300 1.518E-04 301 3.355E-04 302 2.197E-04 303 3.240E-04 ... ``` Function `read_licor_prn` will automatically detect whether the data is energy or photon based. In all cases as much metadata information as possible is decoded, and the data file headers are preserved as comments in the source.spct objects. **The missing information for year is set to zero in the `when.measured` attribute, with month, day, hours and minutes as decoded from the header. The time zone defaults to UTC and will need in general to be passed as an argument to `tz` in the function call.** ```{r} licor.file <- system.file("extdata", "spectrum.PRN", package = "photobiologyInOut", mustWork = TRUE) licor.spct <- read_licor_prn(file = licor.file, tz = "EET") ``` Even when using to correct argument for `tz` the time will still default to UTC when the spectrum is printed or plotted, but this time expressed in UTC may still be shifted from the correct time in the time zone where measurements were acquired as without year information it is impossible to adjust for daylight saving time and other shifts in local times that have changed over the years as a result of changes in legislation. ```{r} licor.spct cat(comment(licor.spct)) autoplot(licor.spct, unit.out = "photon") ``` It is also possible to use the same function to import reflectance, and transmittance spectra acquired by the LI-1800. And a spectral reflectance output file generated by LI-COR's PC1800 program for the LI-1800 spectroradiometer is used next. The first few lines of the file look like this: ``` "FILE:RGD1" "REM: REFL GREEN AD 1 " "LIMS: 350- 800NM" "INT: 2NM" "DATE:05/30 13:50" "MIN: 358NM 4.628E-02" "MAX: 776NM 4.693E-01" 350 5.135E-02 352 4.713E-02 354 5.324E-02 356 4.740E-02 ... ``` Function `read_licor_prn` cannot automatically detect the spectral quantity in the file, and when the irradiance default is not correct, users need to override it with an explicit argument for parameter `s.qty`. ```{r} licor.file <- system.file("extdata", "reflectance.PRN", package = "photobiologyInOut", mustWork = TRUE) licor.spct <- read_licor_prn(file = licor.file, s.qty = "Rfr") ``` In all cases as much information as possible is decoded, and the data file headers are preserved as comments in the source.spct objects. ```{r} licor.spct cat(comment(licor.spct)) autoplot(licor.spct) ``` ### The SpectraPen spectroradiometer from PSI This all-in-one spectroradiometer measures spectral irradiance, and returns the data in a `.CSV` file with one column per spectrum. The data are returned expressed in energy or photon based units. The first few lines of a data block look like this: ``` Irradiance [µW/cm2/nm], Time,11/10/2022 7:08:01 PM,11/10/2022 7:08:05 PM,11/10/2022 7:08:10 PM,11/10/2022 7:08:32 PM,11/10/2022 7:08:36 PM,11/10/2022 7:08:42 PM, Index,13,14,15,16,17,18, Name,,,,,,, GPS,,,,,,, [nm], 327.1,3.733005E+000,3.711488E+000,3.914620E+000,9.741472E+000,9.176950E+000,1.050528E+001 329,3.557857E+000,3.256521E+000,3.686638E+000,8.320147E+000,8.764947E+000,8.995773E+000 330.8,3.250507E+000,2.988691E+000,3.100541E+000,7.933364E+000,8.187113E+000,8.819886E+000 ... ``` or ``` Irradiance [µE/m2/s/nm], Time,11/10/2022 7:08:01 PM,11/10/2022 7:08:05 PM,11/10/2022 7:08:10 PM,11/10/2022 7:08:32 PM,11/10/2022 7:08:36 PM,11/10/2022 7:08:42 PM, Index,13,14,15,16,17,18, Name,,,,,,, GPS,,,,,,, [nm], 327.1,1.020666E-001,1.014783E-001,1.070323E-001,2.663483E-001,2.509133E-001,2.872321E-001 329,9.783817E-002,8.955168E-002,1.013796E-001,2.287973E-001,2.410289E-001,2.473764E-001 330.8,8.989830E-002,8.265734E-002,8.575075E-002,2.194107E-001,2.264286E-001,2.439290E-001 ``` ```{r} file.name <- system.file("extdata", "spectrum-psi-spectrapen-SP.csv", package = "photobiologyInOut", mustWork = TRUE) psi.mspct <- read_spectrapen_csv(file = file.name, tz = "UTC") summary(psi.mspct) autoplot(psi.mspct, annotations = "") ``` ```{r} summary(psi.mspct[["spct.14"]]) autoplot(psi.mspct[["spct.14"]]) ``` **Note:** It is clear from the figure above that this spectrometer suffers badly from straylight in the UV-A region, and readings at wavelengths shorter than 400 nm in the presence of stronger radiation at longer wavelengths are to be discarded. ### The leaf spectrometer from CID Bio-Science This all-in-one spectrometer measures spectral reflectance, spectral transmittance or spectral absorbance of plant leaves or in fact any thin film. There is a single configuration available and being based on a microcontroller this instrument is used autonomously and spectral data saved internally can be exported as CSV files. Reflectance and transmittance generate a single spectrum per measurement while absorbance generates three: spectral absorbance, spectral reflectance and spectral transmittance. The last two are needed to compute absorbance, and, wisely, they are also returned. In the case of absorbance measurements it is possible to import the data into an `object_spct` containing variables `Rfr` and `Tfr` or as separate objects. ```{r} file.name <- system.file("extdata", "cid-spectravue-Rpc-Measurements.csv", package = "photobiologyInOut", mustWork = TRUE) cid_Rpc.spct <- read_cid_spectravue_csv(file = file.name) summary(cid_Rpc.spct) autoplot(smooth_spct(cid_Rpc.spct, method = "supsmu"), range = c(400, 1000), annotations = "") %+% ylim(0, 0.55) ``` ## Data from loggers ### Campbell Scientific [Campbell Scientific](https://www.campbellsci.eu/) is a well know supplier of data loggers for commercial and research applications. Function `read_csi_dat()` defined in this package has been tested with a recent datalogger model, the CR6, and using recent versions of programs PC400 and PC200W to download the data. The currently used format of .DAT files is easy to decode and our function can automatically detect the number and type of columns and the number of rows. ```{r} cs.day.file <- system.file("extdata", "cr6-day.dat", package = "photobiologyInOut", mustWork = TRUE) ``` Executing the statement below displays the 10 top lines of the DAT file as is, one character string per line. ```{r, eval=FALSE} # not run read_lines(yoctopuce_hour.file, n_max = 10) ``` ```{r} day.dat <- read_csi_dat(file = cs.day.file) day.dat ``` All information is preserved in the returned `tibble::tibble` object, which is derived from `data.frame`. ```{r} cs_hour.file <- system.file("extdata", "cr6-hour.dat", package = "photobiologyInOut", mustWork = TRUE) hour.dat <- read_csi_dat(file = cs_hour.file) ggplot(hour.dat, aes(TIMESTAMP, PAR_Den_Avg)) + geom_line() ``` ### YoctoPuce [Yocto Puce Sarl](https://www.yoctopuce.com/) sells numerous different USB modules. Those capable of data input can log the data to memory and these data can be downloaded as a CSV file. These files can be easily read into R using base functions but function `read_yoctopuce_csv()` makes this even a bit simpler. ```{r} yoctopuce_hour.file <- system.file("extdata", "yoctopuce-data.csv", package = "photobiologyInOut", mustWork = TRUE) ``` Executing the statement below displays the 10 top lines of the CSV file as is, one character string per line. ```{r, eval=FALSE} # not run read_lines(yoctopuce_hour.file, n_max = 10) ``` Here we import and plot the data. ```{r} hour.dat <- read_yoctopuce_csv(file = yoctopuce_hour.file) ggplot(hour.dat, aes(ISO.time, temperature.avg)) + geom_line() ``` ## Output from simulation models Functions for importing simulated spectral data. | R function | Simulation model | Version | `class` of value | |:-----------------------|:-----------------------|:------------------|:-----------------| | read_tuv_usrout() | TUV (S. Madronich) | version 5.0 | source_spct | | read_tuv_usrout2mspct() | TUV (S. Madronich) | version 5.0 | source_mspct | | read_qtuv_txt() | TUV (S. Madronich) | version 5.2 | source_spct | | read_uvspec_disort() | libRadtran | irradiance | source_spct | | read_uvspec_vesa() | (T. & V. Kotilainen) | irradiance | source_spct | | read_fmi_cum() | (A. Lindfors) | daily cumulated | source_spct | | read_m_fmi_cum() | (A. Lindfors) | daily cumulated | source_mspct | ### TUV The output from the TUV model can be imported either by editing it before import, or by making a simple edit to the output routine of TUV. This function is known to work with TUV version 5.0 output. The output from TUV can contain a variable number of spectra in ''parallel'' columns, which are _melted_ into a single column, with a factor with letters as levels, a numeric variable with the zenith angle and a POSIXct column with times. A date needs to be always supplied as the output file from TUV has only time of day information. ```{r} tuv.file <- system.file("extdata", "usrout.txt", package = "photobiologyInOut", mustWork = TRUE) tuv.spct <- read_tuv_usrout(file = tuv.file, date = ymd("2014-03-21")) summary(subset(tuv.spct, spct.idx == "A")) tuv.spct ``` It is possible to extract individual spectra with subset, or as done here plot them in different panels. ```{r, fig.height=10} autoplot(tuv.spct, annotations = c("colour.guide")) + facet_wrap(~as.character(date), ncol = 2) ``` The output is a single `source_spct} object that can be easily converted into a `source_mspct} object containing the individual spectra as members of the collection. ```{r} tuv.mspct <- subset2mspct(tuv.spct) summary(tuv.mspct) autoplot(tuv.mspct) ``` A file can be directly read into a collection using `read_tuv_usrout2mspct()` which is a simple wrapper. With the default of `lubridate::today()` date times are 'mapped' to the current local date using the time zone of the computer as visible to R. **This is unlikely to be correct!** ```{r} tuv_nd.spct <- read_tuv_usrout(file = tuv.file) when_measured(tuv_nd.spct) ``` ### Quick TUV calculator The files output by the online calculator based on the TUV model, contain at most one spectrum, and arguments to only some parameters can be set by users. However, it is convenient to use when we only need a few simple simulations. Function `read_qtuv_txt()` can extract spectra and the corresponding metadata from these files. These files do contain date time information and geolocation data when they are supplied as arguments to the calculator interface, otherwise only zenith angle is available. ```{r} qtuv.file <- system.file("extdata", "qtuv.txt", package = "photobiologyInOut", mustWork = TRUE) qtuv.spct <- read_qtuv_txt(file = qtuv.file) summary(qtuv.spct) qtuv.spct ``` ### libRadtran By default libRadtran's uvspec writes only spectral irradiances to a text file as output. This is different from 'TUV' which by default includes an extensive header with the parameter settings used for the simulation. It is easy to read this simple output file with R's functions. However, we provide functions, that simplify reading of the files. The output from uvspec varies depending on its input. The main source of differences is the solver routine used. We will provide a separate function for each solver. For reading this simple output, no special function is needed. We can use `read.table` from base R. Here we read a file with two columns with wavelengths and global spectral energy irradiance (named "eglo" in libRadtran) in $mW\,m^{-2}\,nm^{-1}$. The file was created with one of the 'uvspec' examples included with libRadtran, but reducing the output to two columns. The first few lines of the file look like this: ``` 250.000 0.000000e+00 251.000 0.000000e+00 252.000 0.000000e+00 253.000 0.000000e+00 ... ``` ```{r} uvspec.2col.file <- system.file("extdata", "uvspec-plain-2col.dat", package = "photobiologyInOut", mustWork = TRUE) lrt.df <- read.table(file = uvspec.2col.file, col.names = c("w.length", "s.e.irrad")) uvspec.01.spct <- source_spct(w.length = lrt.df$w.length, s.e.irrad = lrt.df$s.e.irrad * 1e-3) summary(uvspec.01.spct) cat(comment(uvspec.01.spct)) autoplot(uvspec.01.spct, range = c(250, 2500), unit.out = "photon") ``` An example using solver `disort` and our function read_uvspec_disort() follows. The first few lines of the file look like this: ``` 290.000 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 291.000 1.046525e-11 4.800521e-06 1.674293e-07 2.374267e-12 5.342789e-07 2.664720e-08 292.000 5.888299e-10 2.813865e-05 9.814190e-07 1.335888e-10 3.162808e-06 1.561977e-07 293.000 4.383296e-09 5.764524e-05 2.010660e-06 9.944455e-10 6.522616e-06 3.200065e-07 ... ``` ```{r} uvspec.disort.file <- system.file("extdata", "uvspec-disort.dat", package = "photobiologyInOut", mustWork = TRUE) uvspec.02.spct <- read_uvspec_disort(uvspec.disort.file) summary(uvspec.02.spct) cat(comment(uvspec.02.spct)) autoplot(uvspec.02.spct, unit.out = "photon") ``` The data contains also estimates of diffuse and direct spectral irradiance. Here we plot the total energy irradiance with a solid line and the diffuse component with a dashed line. ```{r} ggplot(uvspec.02.spct) + geom_line() + geom_line(aes(y = s.e.irrad.diff), linetype = "dashed") ``` The uvspec file used to generate the spectrum read above is: ``` data_files_path uvspec_home/data/ atmosphere_file uvspec_home/data/atmmod/afglms.dat source solar uvspec_home/data/solar_flux/kurudz_1.0nm.dat rte_solver disort mol_abs_param lowtran deltam on number_of_streams 6 wavelength 290 900 day_of_year 287 altitude 0.012 albedo_library IGBP brdf_rpv_type 5 mol_modify O3 288 DU mol_modify H2O 10 MM sza 69.4662 sur_temperature 273 ``` If we plan to save and reuse the spectral object, it is recommended to append the input file to the comment. ```{r} uvspec.disort.inp.file <- system.file("extdata", "uvspec-disort.inp", package = "photobiologyInOut", mustWork = TRUE) comment(uvspec.02.spct) <- paste(comment(uvspec.02.spct), read_file(uvspec.disort.inp.file), sep = "\n\n") cat(comment(uvspec.02.spct)) ``` We give two additional examples, which will most likely need some adjustment by users, as these are for output from libRadtran post-processed to add additional information. These are included in the package because myself and collaborators use these formats heavily. In fact users could develop shell scripts or Perl scripts using the same output format. ### Output enriched with time and date data In this case the file to be read is similar as above, but including separate columns for direct and diffuse components of the spectral energy irradiance. In addition two columns, one with date strings in ISO format and one with times have been added. The file instead of containing a single spectrum, contains several spectra in long form. The first few lines of the file look like this: ``` 290.000 2015-05-19 11_00_00 0.000000e+00 0.000000e+00 291.000 2015-05-19 11_00_00 0.000000e+00 0.000000e+00 292.000 2015-05-19 11_00_00 0.000000e+00 0.000000e+00 293.000 2015-05-19 11_00_00 1.893645e-05 3.439497e-05 294.000 2015-05-19 11_00_00 1.648530e-04 2.764368e-04 ... ``` A function is included for reading data saved in a text file in this format. It also automatically converts $mW\,m^{-2}\,nm^{-1}$ into $W\,m^{-2}\,nm^{-1}$. ```{r} uvspec.multi.file <- system.file("extdata", "uvspec-multi.dat", package = "photobiologyInOut", mustWork = TRUE) lbr.multi.spct <- read_uvspec_disort_vesa(uvspec.multi.file) print(lbr.multi.spct, n = 5) ``` ### Scripts developed by Anders Lindfors A model for the simulation of the solar spectrum was developed at the Finnish Meteorological Institute (FMI) by Dr.\ Anders Lindfors and collaborators and uses functions from 'libRadtran' as its engine, but saves some additional metadata to the output file. The main addition is related to the estimation of the effect of clouds. Functions `read_fmi_cum()` and `read_m_fmi_cum()` can be used to read text files output as daily integrated spectral irradiance. In other words cummulated daily data. Function `read_fmi2mspct()` reads spectral irradiance, extracting multiple sequential spectra from a single file. The first few lines of the files with cummulated data look like this: ``` # date number_of_scans start_scan stop_scan max_time_gap max_sza_gap warnings # 20140821 15 3:30:00 17:30:00 60 7.4 # wavelength exposure(J/m2/nm) 2900 0.00000000e+00 2910 2.93132235e-05 2920 7.23526379e-04 ... ``` We can read an individual file into a `source_spct` object while adding some metadata read from the file header. In this case values are for daily global spectral energy exposures rather than irradiances. Wavelengths are expressed in Angstroms instead of nanometres. ```{r} fmi.file <- system.file("extdata", "2014-08-21_cum.hel", package = "photobiologyInOut", mustWork = TRUE) z.spct <- read_fmi_cum(fmi.file) class_spct(z.spct) getWhenMeasured(z.spct) z.spct ``` With function `read_m_fmi_cum` with an ``m'' in the name we can read several files each containing a single spectrum. The returned object is a collection of source spectra. ```{r} fmi.files <- system.file("extdata", c("2014-08-21_cum.hel", "2014-08-21_cum.hel"), package = "photobiologyInOut", mustWork = TRUE) z.mspct <- read_m_fmi_cum(fmi.files) class(z.mspct) getWhenMeasured(z.mspct) z.mspct ``` Above we gave the names of the files explicitly, but as we show here, one can build on-the-fly a list of file names matching some pattern. The example below is not run, as the location of example files may vary. The string `"."` should be replaced with the path to the folder where the files to be read are located. ```{r, eval=FALSE} fmi.files <- list.files(".", "*cum.hel") fmi.files <- paste(".", fmi.files, sep = "") z1.mspct <- read_m_fmi_cum(fmi.files) class(z1.mspct) getWhenMeasured(z1.mspct) z1.mspct ``` One also add a geocode at the time of import (or later). ```{r, message=FALSE} # because of Google's query limits call will frequently fail without a key # my.geocode <- ggmap::geocode("Kumpula, Helsinki, Finland", source = "google") my.geocode <- data.frame(lon = 24.96474, lat = 60.20911) z2.mspct <- read_m_fmi_cum(fmi.files, geocode = my.geocode) class(z2.mspct) getWhenMeasured(z2.mspct) getWhereMeasured(z2.mspct) z2.mspct ``` Files with spectral irradiance contain data for multiple spectra stored as text. Each spectrum is delimited at the top by a header line with metadata and at the end by `"end"` in a line by itself. The first few and last lines for each spectrum look like this: ``` # 20130501 3:30:00 3:30:00 82.656 210.00 2900 0 210.00 2910 0 210.00 2920 0 ... 210.00 8480 103.73018 210.00 8490 104.63495 210.00 8500 90.18384 end ... ``` The number of spectra, range of wavelengths and the length of each spectrum can vary. Function `read_fmi2mspct()` uses matching to the delimiters to read all the data in all cases. ```{r} fmi.file <- system.file("extdata", "2013-05-01.hel", package = "photobiologyInOut", mustWork = TRUE) z3.mspct <- read_fmi2mspct(fmi.file) class(z3.mspct)[1:2] getWhenMeasured(z3.mspct[[1]]) length(z3.mspct) names(z3.mspct) getWhenMeasured(z3.mspct[[1]]) getWhatMeasured(z3.mspct[[1]]) ``` ## Online public repositories of spectral data Functions for importing spectral data downloaded from repositories. | R function | Data repository | Version | `class` of value | |:-----------------------|:-----------------------|:------------------|:-----------------| | read_FReD_csv() | Floral Reflectance db. | 2017-03-19 | reflector_spct | | read_ASTER_txt() | ASTER spectral lib. | version 2.0 ASCII | reflector_spct | ### FReD Floral Reflectance Database The files downloaded from FReD do not contain a header, but the first column indicates the flower ID. ``` 157, 300, 0.0627119 157, 301, 0.0654036 157, 302, 0.0677941 157, 303, 0.0670396 ... ``` ```{r} fred.file <- system.file("extdata", "FReDflowerID_157.csv", package = "photobiologyInOut", mustWork = TRUE) fred.spct <- read_FReD_csv(file = fred.file, label = "Gazania heterochaeta", geocode = data.frame(lat = -28.8751, lon = 17.2293)) ``` In this case as there is no metadata present in the file, it needs to be supplied by the user. ```{r} fred.spct cat(comment(fred.spct)) autoplot(fred.spct) ``` ### ASTER spectral database The files downloaded from ASTER contain a 25-lines-long header, but at the moment only the first field is decoded, as the whole header copied as a comment. ``` Name: Dry grass Type: Vegetation Class: Grasses Subclass: Dry grass Particle Size: Solid Sample No.: drygrass.doc Owner: JHU Wavelength Range: All Origin: The entire spectral range was measured at Johns Hopkins University. Description: Dry grass. Spectra were assembled from two segments; the bidirectional VNIR and SWIR comprising segment one, and the hemispherical MWIR and TIR comprising segment two. The VNIR/SWIR spectrum was measured in the laboratory at JHU with a GER IRIS Mark IV, using a large piece of sod. The grass was illuminated from directly above and measured at a reflectance angle of 60 degrees to avoid viewing the thatch. Measurement: Bidirectional and directional hemispherical reflectance. First Column: X Second Column: Y X Units: Wavelength (micrometers) Y Units: Reflectance (percent) First X Value: 0.38049 Last X Value: 14.011 Number of X Values: 2559 Additional Information: None. 0.38049 14.249 0.38299 14.251 0.38544 14.546 0.38791 14.694 ... ``` ```{r} aster.file <- system.file("extdata", "drygrass-spectrum.txt", package = "photobiologyInOut", mustWork = TRUE) aster.spct <- read_ASTER_txt(file = aster.file) ``` The label and comment are set from the file header. ```{r} aster.spct cat(comment(aster.spct)) autoplot(aster.spct) ``` ## Other R packages A general way of exchanging data with other R packages or for use with base R functions is to create a matrix from a collection of spectra with `as.matrix()`, or a collection of spectra from a matrix with one of the `as.xxxx_mspct()` methods such as `as.source_spct`. Such methods are defined in package 'photobiology' as well as method `join_mspct()` for conversion of collections of spectra into _wide_ data frames. However, a matrix is only guaranteed to contain numeric data and a `"dim"` attribute, while conversion to a data frame preserves only part of the metadata. These generic conversions cannot be reversed without loss of information. When possible use the package specific functions as they automate much of the recovery and preservation of metadata. Functions for exchanging data with _foreign_ R packages. | R function | Foreign R package | Function | `class` of value | |:-----------------------|:-----------------------|:------------------|:-----------------| | hyperSpec2spct() | ’hyperSpec’ | import | source_spct | | spct2hyperSpec() | ’hyperSpec’ | export | hyperSpec | | hyperSpec2mspct() | ’hyperSpec’ | import | source_mspct | | mspct2hyperSpec() | ’hyperSpec’ | export | hyperSpec | | colorSpec2spct() | ’colorSpec’ | import | source_spct | | spct2colorSpec() | ’colorSpec’ | export | colorSpec | | colorSpec2mspct() | ’colorSpec’ | import | source_mspct | | mspct2colorSpec() | ’colorSpec’ | export | colorSpec | | chroma_spct2colorSpec() | ’colorSpec’ | export | colorSpec | | rspec2mspct() | ’pavo’ | import | source_mspct | ### To 'hyperSpec' Can export to `''hyperSpec''` objects only collections of spectra where all members have identical `w.length` vectors, as objects of class `hyperSpec` store a single vector of wavelengths for the whole collection of spectra. ```{r, eval=eval_hyperSpec} z2.hspct <- mspct2hyperSpec(z2.mspct, "s.e.irrad") class(z2.hspct) # plot(z2.hspct) ``` ### From 'hyperSpec' Can import only data with wavelength in nanometres. Other quantities and units are not supported by the 'photobiology' classes for spectral data. See package 'hyperSpec' vignette "laser" for details on the data and the conversion of the original wavelength units into nanometres. ```{r, eval=eval_hyperSpec} data(laser) class(laser) laser plot(laser) ``` We assume here, that the quantity for the spectral emission of the laser is spectral _energy_ irradiance, expressed in $mW\,m^{-2}\,nm^{-1}$. This is likely to be wrong but for the sake of showing how the conversion takes place is irrelevant. The parameter `multiplier` can be passed a numeric argument to rescale the original data. The default multiplier is 1. ```{r, eval=eval_hyperSpec} wl(laser) <- list ( wl = 1e7 / (1/405e-7 - wl (laser)), label = expression (lambda / nm) ) laser plot(laser) laser.mspct <- hyperSpec2mspct(laser, "source_spct", "s.e.irrad", multiplier = 1e-3) ggplot(laser.mspct[[1]]) + geom_line() + stat_peaks(geom = "text", vjust = -1, label.fmt = "%.6g nm", color = "red") ``` ### From 'colorSpec' ```{r, eval = eval_colorSpec} # bug that needs to be fixed fluorescent.mspct <- colorSpec2mspct(colorSpec::Fs.5nm) print(fluorescent.mspct, n = 3, n.members = 3) ``` ```{r, eval = eval_colorSpec} colorSpec2mspct(colorSpec::Hoya) ``` ```{r, eval = eval_colorSpec} fluorescent.spct <- colorSpec2spct(colorSpec::Fs.5nm) autoplot(fluorescent.spct, annotations = "") ``` ```{r, eval = eval_colorSpec} colorSpec2chroma_spct(colorSpec::xyz1931.5nm) ``` ### To 'colorSpec' ```{r, eval = eval_colorSpec} sun.cspec <- spct2colorSpec(sun.spct) plot(sun.cspec, col = "blue") ``` ```{r, eval = eval_colorSpec} spct2colorSpec(yellow_gel.spct) ``` ```{r, eval = eval_colorSpec} chroma_spct2colorSpec(beesxyzCMF.spct) ``` ### Wrappers on 'colorSpec' functions. Functions `spct_CCT()`, `spct_CRI()` and `spct_SSI()` call the respective `compute` functions after converting `source_spct` objects. CCT, CRI and SSI are meaningful for human vision although they are used not only for general illumination but also in photography and cinematography. They can be generalized by overriding the default references from human vision with those of cameras or other visual systems. ```{r} spct_CCT(white_led.source_spct) # correlated color temperature spct_CRI(white_led.source_spct) # color rendition index spct_CRI(white_led.source_spct, named = TRUE) spct_SSI(white_led.source_spct, sun.spct) # spectral similarity index ``` ### From 'pavo' In this example we convert an `rspec` object from package 'pavo' into a collection of spectra and then we plot it with `ggplot` methods from package `ggspectra' (an extension to `ggplot2'). The data are the spectral reflectance of the plumage from seven different individual birds of the same species, measured in three different body parts. ```{r, eval = eval_pavo} data(sicalis) class(sicalis) names(sicalis) ``` We convert the data into a collection of spectra, and calculate summaries for three spectra. ```{r, eval = eval_pavo} sicalis.mspct <- rspec2mspct(sicalis, "reflector_spct", "Rpc") summary(sicalis.mspct[[1]]) summary(sicalis.mspct[[2]]) summary(sicalis.mspct[[3]]) ``` We convert the subset of the collection corresponding to the first individual into a single spectra object for plotting with `ggplot`. ```{r, eval = eval_pavo} ggplot(rbindspct(sicalis.mspct[1:3])) + aes(linetype = spct.idx) + ylim(0,0.3) + geom_line() ``` Here we extract the ``crown'' data from all individuals and plot these spectra in a single plot. ```{r, eval = eval_pavo} print(sicalis.mspct[c(TRUE, FALSE, FALSE)]) ggplot(rbindspct(sicalis.mspct[c(TRUE, FALSE, FALSE)])) + aes(linetype = spct.idx) + ylim(0,0.15) + geom_line() + ggtitle("'crown' reflectance spectra") ``` We calculate the mean reflectance in wavebands corresponding to ISO colors obtaining a data frame. We then add to this returned data frame a factor indicating the body parts. ```{r, eval = eval_pavo} refl.by.band <- reflectance(sicalis.mspct, w.band = list(Red(), Green(), Blue(), UVA())) refl.by.band$body.part <- rep(c("crown", "throat", "breast"), 7) ``` ```{r, eval = eval_pavo} refl.red <- reflectance(sicalis.mspct, w.band = Red()) names(refl.red)[2] <- "red.reflectance" refl.red$body.part <- rep(c("crown", "throat", "breast"), 7) ggplot(refl.red, aes(x = body.part, y = red.reflectance)) + stat_summary(fun.data = "mean_se", color = "red") + geom_point(alpha = 0.5) ``` ## Dealing with odd and bad data ### Using locales Most functions in this package have a parameter `locale`, that accepts `readr::locale` objects as arguments. At the moment only the time zone and decimal mark are respected. This allows files using comma for decimal marker be easily imported, or the dates and times **in the input file** be interpreted in a given time zone. Setting the correct time zone is very important to avoid errors. Time coordinates are always stored in the created objects using universal time coordinates ("UTC"). ```{r} jaz.irrad.comma.file <- system.file("extdata", "spectrum-comma.JazIrrad", package = "photobiologyInOut", mustWork = TRUE) my.locale <- locale(decimal_mark = ",", tz = "EET") jaz00.spct <- read_oo_jazirrad(file = jaz.irrad.comma.file, locale = my.locale) ``` ```{r} jaz00.spct ``` ### Overriding default metadata We revisit now the Jaz irradiance data to show how the metadata can be changed by the user if needed (e.g. clock settings at the time of data acquisition were wrong). A variable with the user supplied date and time data, or the date read from the header (the text itself) not the file date as the file date may not reflect the creation date and time. ```{r} jaz.s.irrad.file <- system.file("extdata", "spectrum.JazIrrad", package = "photobiologyInOut", mustWork = TRUE) ``` ```{r, warning=FALSE} jaz01.spct <- read_oo_jazirrad(file = jaz.s.irrad.file, date = NULL) getWhenMeasured(jaz01.spct) ``` ```{r, warning=FALSE} jaz02.spct <- read_oo_jazirrad(file = jaz.s.irrad.file, date = ymd_hms("2015-11-15 12:00:00")) getWhenMeasured(jaz02.spct) ``` ```{r, warning=FALSE} jaz03.spct <- read_oo_jazirrad(file = jaz.s.irrad.file, date = now()) getWhenMeasured(jaz03.spct) ``` ### Adding additional metadata When can add a geocode, either directly by giving latitude and longitude coordinates or by generating it from a Google maps search using function `ggmap::geocode()` as shown here. ```{r, message=FALSE,warning=FALSE} my.geocode <- data.frame(lon = 25.02006, lat = 60.22525) jaz04.spct <- read_oo_jazirrad(file = jaz.s.irrad.file, geocode = my.geocode) jaz04.spct getWhereMeasured(jaz04.spct) ```