{ // PyList_GET_SIZE(self) 展开之后为 ((PyVarObject*)(self))->ob_size Py_ssize_t n = PyList_GET_SIZE(self); assert (v != NULL); // 如果元素的个数已经等于允许的最大的元素个数 就报错 if (n == PY_SSIZE_T_MAX) { PyErr_SetString(PyExc_OverflowError, "cannot add more ...
print(list(r))# [0, 1, 2, 3, 4] r =range(0,10,2) print(list(r))# [0, 2, 4, 6, 8] r =range(10,0, -1) print(list(r))# [10, 9, 8, 7, 6, 5, 4, 3, 2, 1] # 通过 range() 可以创建一个执行指定次数的 for 循环 foriinrange(30): print(i) 序列的通用操作 ...
它们调用obj.__format__(format_spec)以获取使用特殊格式代码的对象的字符串显示。我们将在下一个示例中介绍__bytes__,然后介绍__format__。 警告 如果您从 Python 2 转换而来,请记住,在 Python 3 中,__repr__,__str__和__format__必须始终返回 Unicode 字符串(类型str)。 只有__bytes__应该返回字节序...
* Request in bytes Size of allocated block Size class idx * --- * 1-8 ...
= '': file_list.append(file_name.text) return file_list @ops_conn_operation def get_file_size_form_dir(file_path='', file_dir='', ops_conn=None): """Return the size of a file in the directory under the home directory. """ file_size = 0 src_file_name = os.path.basename(...
四、list类解析 >>> help(list) Help on class list in module builtins: class list(object) |list() -> new empty list |list(iterable) -> new list initialized from iterable's items (可迭代对象,__iter__) | | Methods defined here: ...
empty(空的) string(text) number date boolean error blank(空白表格) 导入模块 import xlrd 打开Excel文件读取数据 data = xlrd.open_workbook(filename)#文件名以及路径,如果路径或者文件名有中文给前面加一个 r 常用的函数 excel中最重要的方法就是book和sheet的操作 ...
>>> a.size 15 >>> type(a) >>> b = np.array([6, 7, 8]) >>> b array([6, 7, 8]) >>> type(b) # End www_512pic_com 二.创建数组: 使用array函数讲tuple和list转为array: >>> import numpy as np >>> a = np.array([2,3,4]) ...
""" x.__rmul__(n) <==> n*x """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ T.__sizeof__() -- size of T in memory, in bytes """ pass 1. 2. 3. 4. 5. 6. 7. 8.
Here are just a few of the things that pandas does well:- Easy handling of missing data in floating point as well as non-floatingpoint data.- Size mutability: columns can be inserted and deleted from DataFrame andhigher dimensional objects- Automatic and explicit data alignment: objects can ...