numpoly.savetxt

numpoly.savetxt(fname: os.PathLike, X: numpoly.typing.PolyLike, fmt: str = '%.18e', delimiter: str = ' ', newline: str = '\n', header: str = '', footer: str = '', comments: str = '# ', encoding: Optional[str] = None)

Save a polynomial array to a text file.

To store a polynomial to text string, the polynomial is converted through a flat structured array, to a matrix. Extra meta information about the indeterminant names, exponent keys and array shape are all stored separate at the top of the header of the output file.

Args:

fname:

If the filename ends in .gz, the file is automatically saved in compressed gzip format. loadtxt understands gzipped files transparently.

X:

Data to be saved to a text file.

fmt:

A single format (%10.5f), a sequence of formats, or a multi-format string, e.g. ‘Iteration %d – %10.5f’, in which case delimiter is ignored. For complex X, the legal options for fmt are:

• A single specifier, fmt=’%.4e’, resulting in numbers formatted like ‘ (%s+%sj)’ % (fmt, fmt).

• A full string specifying every real and imaginary part, e.g. ‘ %.4e %+.4ej %.4e %+.4ej %.4e %+.4ej’ for 3 columns.

• A list of specifiers, one per column - in this case, the real and imaginary part must have separate specifiers, e.g. [‘%.3e + %.3ej’, ‘(%.15e%+.15ej)’] for 2 columns.

delimiter:

String or character separating columns.

newline:

String or character separating lines.

header:

String that will be written at the beginning of the file.

footer:

String that will be written at the end of the file.

comments:

String that will be prepended to the header and footer strings, to mark them as comments. Default: ‘# ‘, as expected by e.g. numpoly.loadtxt.

encoding:

Encoding used to encode the outputfile. Does not apply to output streams. If the encoding is something other than ‘bytes’ or ‘latin1’ you will not be able to load the file in NumPy versions < 1.14. Default is ‘latin1’.

Example:

>>> q0, q1 = numpoly.variable(2)
>>> poly = numpoly.polynomial([1, q0, q1**2-1])
>>> numpoly.savetxt("/tmp/poly.txt", poly)
>>> numpoly.loadtxt("/tmp/poly.txt")
polynomial([1.0, q0, q1**2-1.0])
>>> numpoly.savetxt("/tmp/poly.txt", poly, header="my header")
>>> numpoly.loadtxt("/tmp/poly.txt", skiprows=1)
polynomial([1.0, q0, q1**2-1.0])