Call Python Function WithstrInput Arguments

To call a Python function that takes astrinput argument, pass a MATLAB string or a character vector. MATLAB automatically converts the values to the Pythonstrtype.

For example, the Pythonos.listdirfunction gets information about the contents of a folder, specified as typestr. Create a character vector representing a valid folder and callos.listdir. The number of example folders is based on your installed product.

folder = fullfile(matlabroot,'help','examples'); F = py.os.listdir(folder); exFolders = py.len(F)

exFolders = Python int with properties: denominator: [1×1 py.int] imag: [1×1 py.int] numerator: [1×1 py.int] real: [1×1 py.int] 267

Use PythonstrType in MATLAB

In MATLAB, a Python string is apy.strvariable. To use this variable in MATLAB, callchar. For example, the Pythonos.path.pathsepfunction returns the Python path separator character, a semicolon (;).

p = py.os.path.pathsep

p = Python str with no properties. ;

To insert this character between path names, type:

['mypath'char(p)'nextpath']

ans = 'mypath;nextpath'

Read Elements in Python String

You can index into a Python string the same way you index into a MATLAB string. Create a MATLAB character vector and display a range of characters.

str ='myfile'; str(2:end)

ans = 'yfile'

Convert the character vector to a Pythonstrtype and display the same characters.

pstr = py.str(str); pstr(2:end)

ans = Python str with no properties. yfile

Pass MATLAB Backslash Control Character

To pass the backslash control character (\) as a Pythonstrtype, insert the new line control character\nby calling the MATLABsprintffunction. Python replaces\nwith a new line.

py.str(sprintf('The rain\nin Spain.'))

ans = Python str with no properties. The rain in Spain.

Without thesprintffunction, both MATLAB and Python interpret\as a literal backslash.

py.str('The rain\nin Spain.')

ans = Python str with no properties. The rain\nin Spain.

Pass this string to the Python string methodsplit. Python treats the MATLAB character vector as araw stringand adds a\character to preserve the original backslash.

split(py.str('The rain\nin Spain.'))

ans = Python list with no properties. ['The', 'rain\\nin', 'Spain.']