Python

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異常異常（Exception）是因為程式的例外、違例、出錯等情況而在正常控制流程以外採取的行為，一般分為如下兩個階段：1.異常發生：一個錯誤發生後被列印出來，稱為未處理異常，而預設的處理則是自動輸出一些調試資訊並終止程式運行。2.異常處理：通過代碼明確地處理異常，則程式不會終止運行，並增強程式的容錯性。說白了，異常處理的目的就是為了是程式的可執行性更高，能順利的運行下去；同時不讓使用者看到難堪的錯誤資訊，通俗來說就是不讓使用者看見大黃頁。可以通過python3中的異常類型（Exception）查

sqlite3本身並沒有像pymysql一樣原生提供字典形式的遊標。cursor = conn.cursor(pymysql.cursors.DictCursor)但官方文檔裡已經有預留了相應的實現方案。def dict_factory(cursor, row): d = {} for idx, col in enumerate(cursor.description): d[col[0]] = row[idx] return

這篇文章詳解Python cumsums和cumprod函數使用方法>>>a = np.array([1,2,3],[4,5,6]])>>>aarray([[1,2,3], [4,5,6]])>>>a.cumsum(0)array([[1,2,3], [5,7,9]])>>>a.cumprod(1)array([[1,2,6], [4,20,120]])這兩個函數中痛點就是其中參數0,1

英文文檔：all(iterable) Return True if all elements of the iterable are true (or if the iterable is empty). Equivalent to:def all(iterable): for element in iterable: if not element: return False return True說明： 1.

英文文檔：any(iterable) Return True if any element of the iterable is true. If the iterable is empty, return False. Equivalent to:def any(iterable): for element in iterable: if element: return True return False說明： 1.

英文文檔：ascii(object) As repr(), return a string containing a printable representation of an object, but escape the non-ASCII characters in the string returned by repr() using \x, \u or \U escapes. This generates a string similar to that returned

英文文檔：bin(x) Convert an integer number to a binary string. The result is a valid Python expression. If x is not a Python int object, it has to define an __index__() method that returns an integer.說明： 1. 將一個整形數字轉換成二進位字串>>> b = bin(3)

英文文檔：class bool([x]) Return a Boolean value, i.e. one of True or False. x is converted using the standard truth testing procedure. If x is false or omitted, this returns False; otherwise it returns True. The bool class is a subclass of int (see

簡介官方描述：Functional tools for creating and using iterators.即用於建立高效迭代器的函數。itertools.chain(*iterable)將多個序列作為一個單獨的序列返回。例如：import itertoolsfor each in itertools.chain('i', 'love', 'python'): print

英文文檔：class bytearray([source[, encoding[, errors]]])Return a new array of bytes. The bytearray class is a mutable sequence of integers in the range 0 <= x < 256. It has most of the usual methods of mutable sequences, described in Mutable

英文文檔：class bytes([source[, encoding[, errors]]]) Return a new “bytes” object, which is an immutable sequence of integers in the range 0 <= x < 256. bytes is an immutable version of bytearray – it has the same non-mutating methods and the

英文文檔：format(value[, format_spec]) Convert a value to a “formatted” representation, as controlled by format_spec. The interpretation of format_spec will depend on the type of the value argument, however there is a standard formatting syntax that is

英文文檔：class frozenset([iterable])Return a new frozenset object, optionally with elements taken from iterable. frozenset is a built-in class. See frozenset and Set Types — set, frozenset for documentation about this class.For other containers see the

英文文檔：getattr(object, name[, default])Return the value of the named attribute of object. name must be a string. If the string is the name of one of the object’s attributes, the result is the value of that attribute. For example, getattr(x,

英文文檔：globals()Return a dictionary representing the current global symbol table. This is always the dictionary of the current module (inside a function or method, this is the module where it is defined, not the module from which it is called).說明：　　1.

英文文檔：hasattr(object, name)The arguments are an object and a string. The result is True if the string is the name of one of the object’s attributes, False if not. (This is implemented by calling getattr(object, name) and seeing whether it raises an

英文文檔：hash(object)Return the hash value of the object (if it has one). Hash values are integers. They are used to quickly compare dictionary keys during a dictionary lookup. Numeric values that compare equal have the same hash value (even if they are

英文文檔：help([object]) Invoke the built-in help system. (This function is intended for interactive use.) If no argument is given, the interactive help system starts on the interpreter console. If the argument is a string, then the string is looked up

總結一下內建函數，Build-in Function。一、數學運算類abs(x)求絕對值complex([real[, imag]])建立一個複數pmod(a, b)分別取商和餘數注意：整型、浮點型都可以float([x])將一個字串或數轉換為浮點數。如果無參數將返回0.0int([x[, base]]) 將一個字元轉換為int類型，base表示進位long([x[, base]]) 將一個字元轉換為long類型pow(x, y[, z]) 返回x的y次冪range([start], stop[