for example, if we have a text that’s too long to display and we want to show just a portion of it. Or if we want to make an acronym by taking the first letter of each word in a phrase. We can do that through an operation calledstring indexing.This...
defoverspeed_rate(current,max,min):ifcurrent>max:return(current-max)/max # 超过最大时速,结果为正 elif current<min:return(current-min)/min # 超过最小时速,结果为负else:return0# 不超速,结果为0 这个函数用来判断车辆在高速上行驶时超速的比例。它接受三个参数,current表示当前时速,max参数表示当前路段...
Return a copy of the string with leading characters removed. The chars argument is a string specifying the set of characters to be removed. If omitted or None, the chars argument defaults to removing whitespace. The chars argument is not a prefix; rather, all combinations of its values are ...
import collections def _upper(key): #① try: return key.upper() except AttributeError: return key class UpperCaseMixin: #② def __setitem__(self, key, item): super().__setitem__(_upper(key), item) def __getitem__(self, key): return super().__getitem__(_upper(key)) def get(...
IndexError: string index out of range 出现IndexError的原因,是在 'banana' 中没有索引为6的字母。 由于我们从0开始计数,六个字母的编号是0到5。 为了获得最后一个字符,你必须将 length 减一:>>> last = fruit[length-1]>>> last'a' 或者你可以使用负索引,即从字符串的结尾往后数。表达式 fruit[-1...
def decapitalize_first_letter(s, upper_rest=False): # Join the first letter in lowercase with the rest of the string, optionally capitalizing the rest return ''.join([s[:1].lower(), (s[1:].upper() if upper_rest else s[1:])]) ...
5.4 格式化输出(print(f"string={}")) 在Python 中,print(f"string={}") 是一种用于格式化字符串的语法结构。其中,“string”表示字符串;“f”前缀表示这是一个格式化字符串;“{}”是占位符,用于指示将要插入该位置的变量。注意:“f”后面一定要紧跟字符串,不能隔有空格,否则会报错。 a = 1 b = 2 ...
2.2 Parameter of capitalize() The capitalize() method does not take any parameters. 2.3 Return Value The capitalize() method is called directly on the string object and returns a new string with the first character capitalized. 3. Capitalize the First Letter of String using capitalize() ...
3. Get string of first and last 2 chars. Write a Python program to get a string made of the first 2 and last 2 characters of a given string. If the string length is less than 2, return the empty string instead. Sample String : 'w3resource' ...
Replacement field: each of the curly brace components (between{and}) in an f-string is called a replacement field Conversion field: this "converts" the object within a replacement field using a specific converter and it's preceded by an exclamation mark (!) ...