`echemdbconverters.csvloader`

Loader for CSV files (https://datatracker.ietf.org/doc/html/rfc4180) which consist of a single header line containing the column (field) names and rows with comma separated values.

In pandas the names of the columns are referred to as column_names, whereas in a frictionless datapackage the column names are called fields. The datapackage contains information about, i.e., the type of data, a title and a set of descriptors.

The CSV object has the following properties:

TODO:: Add examples for the following functions

a DataFrame
the column names
the header contents
the number of header lines

Loaders for non standard CSV files can be called:

TODO:: Add example

class echemdbconverters.csvloader.CSVloader(file)

Loads a CSV, where the first line must contain the column (field) names and the following lines comma separated values.

EXAMPLES:

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> csv.df
   a  b
0  0  0
1  1  1

A list of column names:

>>> csv.column_names
['a', 'b']

More specific converters can be selected:

TODO:: Add example with csv.get_device(‘device’)(file)

augment(metadata=None)

Metadata constructed from input metadata and the CSV header. A simple CSV does not have any metadata in the header.

EXAMPLES:

Without metadata:

>>> from io import StringIO
>>> file = StringIO(r'''t,E,j
... 0,0,0
... 1,1,1''')
>>> from echemdbconverters.csvloader import CSVloader
>>> csv = CSVloader(file)
>>> csv.augment()
{}

Without metadata provided to the loader:

>>> from io import StringIO
>>> file = StringIO(r'''t,E,j
... 0,0,0
... 1,1,1''')
>>> from echemdbconverters.csvloader import CSVloader
>>> csv = CSVloader(file)
>>> csv.augment(metadata={'foo':'bar'})
{'foo': 'bar'}

property column_names

List of column (field) names describing the tabulated data.

EXAMPLES:

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> csv.column_names
['a', 'b']

static create(device=None)

Calls a specific loader based on a given device.

EXAMPLES:

>>> from io import StringIO
>>> file = StringIO('''EC-Lab ASCII FILE
... Nb header lines : 6
...
... Device metadata : some metadata
...
... mode\ttime/s\tEwe/V\t<I>/mA\tcontrol/V
... 2\t0\t0.1\t0\t0
... 2\t1\t1.4\t5\t1
... ''')
>>> csv = CSVloader.create('eclab')(file)
>>> csv.df
mode  time/s Ewe/V  <I>/mA  control/V
0     2       0   0.1       0          0
1     2       1   1.4       5          1

property data

A file like object with the data of the CSV without header lines.

EXAMPLES:

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> type(csv.data)
<class '_io.StringIO'>

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> csv.data.readlines()
['0,0\n', '1,1']

property decimal

The decimal separator in the floats in the CSV data.

EXAMPLES:

Not implemented in the base loader:

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> csv.decimal
Traceback (most recent call last):
...
NotImplementedError

Implementation in a specific device loader:

>>> file = StringIO('''EC-Lab ASCII FILE
... Nb header lines : 6
...
... Device metadata : some metadata
...
... mode\ttime/s\tEwe/V\t<I>/mA\tcontrol/V
... 2\t0\t0,1\t0\t0
... 2\t1\t1,4\t5\t1
... ''')
>>> csv = CSVloader.create('eclab')(file)
>>> csv.decimal
','

property delimiter

The delimiter in the CSV, which is extracted from the first two lines of the CSV data.

EXAMPLES:

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> csv.delimiter
','

property df

A pandas dataframe of the data in the CSV.

EXAMPLES:

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> csv.df
   a  b
0  0  0
1  1  1

property file

A file like object of the loaded CSV.

EXAMPLES::

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> type(csv.file)
<class '_io.StringIO'>

property header

The header of the CSV (column names excluded).

EXAMPLES:

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> csv.header
[]

property header_lines

The number of header lines in a CSV excluding the line with the column names.

EXAMPLES:

Files for the base loader do not have a header:

>>> from io import StringIO
>>> file = StringIO(r'''a,b
... 0,0
... 1,1''')
>>> csv = CSVloader(file)
>>> csv.header_lines
0

Implementation in a specific device loader:

>>> file = StringIO('''EC-Lab ASCII FILE
... Nb header lines : 6
...
... Device metadata : some metadata
...
... mode\ttime/s\tEwe/V\t<I>/mA\tcontrol/V
... 2\t0\t0,1\t0\t0
... 2\t1\t1,4\t5\t1
... ''')
>>> csv = CSVloader.create('eclab')(file)
>>> csv.header_lines
5

echemdbconverters.csvloader

`echemdbconverters.csvloader`