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Writing PyKX data to disk

pykx.write

QWriter

QWriter(q)

Write data using q.

splayed

splayed(root, name, table)

Splays and writes a q table to disk.

Parameters:

Name Type Description Default
root Union[str, Path, k.SymbolAtom]

The path to the root directory of the splayed table.

required
name Union[str, k.SymbolAtom]

The name of the table, which will be written to disk.

required
table Union[k.Table, pd.DataFrame]

A table-like object to be written as a splayed table.

required

Returns:

Type Description
Path

The path to the splayed table on disk.

See Also

q.read.splayed

Examples:

Write a pandas DataFrame to disk as a splayed table in the current directory.

df = pd.DataFrame([[x, 2 * x] for x in range(5)])
q.write.splayed('.', 'splayed_table', df)

Write a pykx.Table to disk as a splayed table at /tmp/splayed_table.

table = q('([] a: 10 20 30 40; b: 114 113 98 121)')
q.write.splayed('/tmp', 'splayed_table', table)

serialized

serialized(path, data)

Writes a q object to a binary data file using q serialization.

This method is a wrapper around the q function set, and as with any q function, arguments which are not pykx.K objects are automatically converted into them.

Parameters:

Name Type Description Default
path Union[str, Path, k.SymbolAtom]

The path to write the q object to.

required
data Any

An object that will be converted to q, then serialized to disk.

required

Returns:

Type Description
Path

A pykx.SymbolAtom that can be used as a file descriptor for the file.

See Also

q.read.serialized

Examples:

Serialize and write a pandas.DataFrame to disk in the current directory.

df = q('([] a: til 5; b: 2 * til 5)').pd()
q.write.serialized('serialized_table', df)

Serialize and write a Python int to disk in the current directory.

q.write.serialized('serialized_int', 145)

csv

csv(path, table, delimiter=',')

Writes a given table to a CSV file.

Parameters:

Name Type Description Default
path Union[str, Path, k.SymbolAtom]

The path to the CSV file.

required
delimiter Optional[Union[str, bytes, k.CharAtom]]

A single character representing the delimeter between values.

','
table Union[k.Table, pd.DataFrame]

A table like object to be written as a csv file.

required

Returns:

Type Description
Path

A pykx.SymbolAtom that can be used as a file descriptor for the file.

See Also

q.read.csv

Examples:

Write a pandas DataFrame to disk as a csv file in the current directory using a comma as a seperator between values.

df = q('([] a: til 5; b: 2 * til 5)').pd()
q.write.csv('example.csv', df)

Write a pykx.Table to disk as a csv file in the current directory using a tab as a seperator between values.

table = q('([] a: 10 20 30 40; b: 114 113 98 121)')
q.write.csv('example.csv', table, '     ')

json

json(path, data)

Writes a JSON representation of the given q object to a file.

Parameters:

Name Type Description Default
path Union[str, Path, k.SymbolAtom]

The path to the JSON file.

required
data Any

Any type to be serialized and written as a JSON file.

required

Returns:

Type Description
Path

A pykx.SymbolAtom that can be used as a file descriptor for the file.

See Also

q.read.json

Examples:

Convert a pandas Dataframe to JSON and then write it to disk in the current directory.

df = q('([] a: til 5; b: 2 * til 5)').pd()
q.write.json('example.json', df)

Convert a Python int to JSON and then write it to disk in the current directory.

q.write.json('example.json', 143)

Convert a Python dictionary to JSON and then write it to disk in the current directory.

dictionary = {'a': 'hello', 'b':'pykx', 'c':2.71}
q.write.json('example.json', dictionary)