Call Python Function That TakeslistInput Arguments

The Pythonlenfunction returns the number of items in a container, which includes alist目的。

py.help('len')

Help on built-in function len in module builtins: len(obj, /) Return the number of items in a container.

Callos.listdirto create a Pythonlist命名的程序P.

P = py.os.listdir(“ C：\ Program Files \ Matlab”）；班级（P）

ans = 'py.list'

Display the number of programs.

py.len（p）

ans = python int具有属性：分母：[1×1 py.int]图像：[1×1 py.int]分子：[1×1 py.int]真实：[1×1 py.int] 9

Display one element.

p {2}

ans = Python str with no properties. R2016b

Index into Python List

Use MATLAB indexing to display elements in a list. For example, display the last element in thelist. MATLAB returns a Pythonlist.

P(end)

ans = Python list with no properties. ['R2021a']

You also can iterate over the list in aforloop.

forn = P disp(n{1})end

Python str with no properties. R2014b Python str with no properties. R2016b Python str with no properties. R2017b Python str with no properties. R2018b Python str with no properties. R2019a Python str with no properties. R2019b Python str with no properties. R2020a Python str with no properties. R2020b Python str with no properties. R2021a

Convert Pythonlist类型对MATLAB类型

This code displays the names inlistPusing MATLAB variables. Callcellto convert the list. The list is made up of Python strings, so call thecharfunction to convert the elements of the cell array.

cP = cell(P);

每个单元格元素名称都是一个python字符串。

class(cP{1})

ans ='py.str'

将Python字符串转换为MATLAB数据。

mlP = string(cell(P));

Display the names.

forn = 1:numel(cP) disp(mlP{n})end

R2014b R2016b R2017b R2018b R2019a R2019b R2020a R2020b R2021a

Use Python List of Numeric Types in MATLAB

pythonlistcontains elements of any type and can contain elements of mixed types. The MATLABdouble此代码中使用的功能假设Python的所有元素listare numeric.

Suppose that you have a Python function that returns alist整数P. To run this code, create the variable with these values.

p = py.list（{int32（1），int32（2），int32（3），int32（4）}）

p =没有属性的python列表。[1，2，3，4]

Display the numeric type of the values.

class(P{1})

ans ='py.int'

ConvertPto a MATLAB cell array.

cP = cell(P);

将单元格数组转换为MATLAB阵列double.

A = cellfun(@double,cP)

A =1×41 2 3 4

Read Element of NestedlistType

This code accesses an element of a Pythonlistvariable containinglistelements. Suppose that you have thislist.

matrix = py.list({{1, 2, 3, 4},{'hello','世界'},{9, 10}});

显示元素'世界'，索引(2,2).

disp(char(matrix{2}{2}))

world

Display Stepped Range of Python Elements

If you use slicing to access elements of a Python object, the format in Python isstart:stop:step. In MATLAB, the syntax is of the form开始：步骤：停止.

li = py.list({'a','bc',1,2,'def'}); li(1:2:end)

ans = Python list with no properties. ['a', 1.0, 'def']