uvvispy.io module

General facilities for input (and output).

In order to work with UVVis data, these data need to be imported into the UVVisPy package. Therefore, the module provides importers for specific file formats.

Another class implemented in this module is the uvvispy.io.DatasetImporterFactory, a prerequisite for recipe-driven data analysis. This factory returns the correct dataset importer for a specific dataset depending on the information provided (usually, a filename).

class uvvispy.io.DatasetImporter(source=None)

Bases: aspecd.io.DatasetImporter

Base class for dataset importers of the UVVisPy package.

This base class takes care of reading the metadata from the corresponding YAML file. There are two options for classes inheriting from this class: either a call to super()._import() or a call to _read_metadata(). As soon as either of these calls exists in the actual importers and a YAML file with the same base name as the source exists, the metadata will be read from this file and mapped to the dataset.

Note that it is a good idea to first read the metadata from this file and afterwards import the raw data, as this way you can easily overwrite values in the metadata that may have gone wrong in the (manually written) metadata file. Usually, parameters provided in the raw data are more reliable, as they are automatically written by the spectrometer software.

class uvvispy.io.ShimadzuASCIIImporter(source=None)

Bases: uvvispy.io.DatasetImporter

Importer for the Shimadzu UVProbe ASCII export file format.

Note that the Shimadzu UV Probe software originally writes a proprietary binary file format that contains a lot of parameters. Unfortunately, there seems no specification of this format available, and asking the vendor for this was so far not successful. The ASCII export format, however, is rather sparse in terms of additional information, besides the numerical data. A typical file will start as follows:

"<filename_without_extension> - RawData"
"Wavelength nm."        "Abs."
300,00  0,322
301,00  0,310
302,00  0,289

The first two lines are obviously header lines, with the first line starting with the filename excluding its extension, here represented by <filename_without_extension>. The second line contains sort of information for the two columns with data. In this particular case, the decimal separator is the comma, not the dot. Otherwise, it would be fairly easy to just use the aspecd.io.TxtImporter.

Note

If an accompanying metadata file (with same basename and “yaml” as extension) is present, its contents will be read automatically and mapped to the dataset.

parameters

Parameters controlling the import

skiprowsint

Number of rows to skip in text file (e.g., header lines)

Type

dict

class uvvispy.io.DatasetImporterFactory

Bases: aspecd.io.DatasetImporterFactory

Factory for creating importer objects based on the source provided.

Often, data are available in different formats, and deciding which importer is appropriate for a given format can be quite involved. To free other classes from having to contain the relevant code, a factory can be used.

Currently, the sole information provided to decide about the appropriate importer is the source (a string). A concrete importer object is returned by the method get_importer(). If no source is provided, an exception will be raised.

If the source string does not match any of the importers handled by this module, the standard importers from the ASpecD framework are checked. See the documentation of the aspecd.io.DatasetImporterFactory base class for details.