cansas_reader

sans.dataloader.readers.cansas_reader

class sans.dataloader.readers.cansas_reader.Reader

Class to load cansas 1D XML files

Dependencies :The CanSas reader requires PyXML 0.8.4 or later.

__init__()

__module__ = 'sans.dataloader.readers.cansas_reader'

_parse_entry()

Parse a SASentry

Parameters:node – SASentry node Returns:Data1D object

_store_content()

Get the content of a xpath location and store the result. The value is treated as a string.

The xpath location might or might not exist. If it does not exist, nothing is done

Parameters:

• location – xpath location to fetch
• node – node to read the data from
• variable – name of the data member to store it in [string]
• storage – data object that has the ‘variable’ data member

Returns:

return a list of errors

_store_float()

Get the content of a xpath location and store the result. Check that the units are compatible with the destination. The value is expected to be a float.

The xpath location might or might not exist. If it does not exist, nothing is done

Parameters:

• location – xpath location to fetch
• node – node to read the data from
• variable – name of the data member to store it in [string]
• storage – data object that has the ‘variable’ data member
• optional – if True, no exception will be raised if unit conversion can’t be done

Raises ValueError:  

raised when the units are not recognized

_to_xml_doc()

Create an XML document to contain the content of a Data1D

Parameters:datainfo – Data1D object

ext = ['.xml', '.XML', '.avex', '.AVEx', '.absx', 'ABSx']

read()

Load data file

Parameters:

path – file path

Returns:

Data1D object if a single SASentry was found, or a list of Data1D objects if multiple entries were found, or None of nothing was found

Raises:

• RuntimeError – when the file can’t be opened
• ValueError – when the length of the data vectors are inconsistent

type = ['CanSAS 1D files (*.xml)|*.xml', 'CanSAS 1D AVE files (*.AVEx)|*.AVEx', 'CanSAS 1D AVE files (*.ABSx)|*.ABSx']

type_name = 'CanSAS 1D'

version = '1.0'

write()

Write the content of a Data1D as a CanSAS XML file

Parameters:

• filename – name of the file to write
• datainfo – Data1D object

sans.dataloader.readers.cansas_reader.get_content()

Get the first instance of the content of a xpath location.

Parameters:

• location – xpath location
• node – node to start at

Returns:

Element, or None

sans.dataloader.readers.cansas_reader.get_float()

Get the content of a node as a float

Parameters:

• location – xpath location
• node – node to start at

sans.dataloader.readers.cansas_reader.write_node()

Parameters:

• doc – document DOM
• parent – parent node
• name – tag of the element
• value – value of the child text node
• attr – attribute dictionary

Returns:

True if something was appended, otherwise False