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利用alias取别名时,=之间不要有空格。
如:
alias xtark='ssh xtark@192.168.31.37'
source devel/setup.sh
注意,使用launch文件的终端窗口每个都要source
for time_step in tqdm(range(self.args.time_steps)):
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Python 直接赋值、浅拷贝和深度拷贝解析 直接赋值:其实就是对象的引用(别名)。 浅拷贝(copy):拷贝父对象,不会拷贝对象的内部的子对象。 深拷贝(deepcopy): copy 模块的 deepcopy 方法,完全拷贝了父对象及其子对象。 字典浅拷贝实例 实例 >>>a = {1: [1,2,3]} >>> b = a.copy() >>> a, b ({1: [1, 2, 3]}, {1: [1, 2, 3]}) >>> a[1].append(4) >>> a, b ({1: [1, 2, 3, 4]}, {1: [1, 2, 3, 4]}) 深度拷贝需要引入 copy 模块: 实例 >>>import copy >>> c = copy.deepcopy(a) >>> a, c ({1: [1, 2, 3, 4]}, {1: [1, 2, 3, 4]}) >>> a[1].append(5) >>> a, c ({1: [1, 2, 3, 4, 5]}, {1: [1, 2, 3, 4]}) 解析 1、b = a: 赋值引用,a 和 b 都指向同一个对象。 2、b = a.copy(): 浅拷贝, a 和 b 是一个独立的对象,但他们的子对象还是指向统一对象(是引用)。 b = copy.deepcopy(a): 深度拷贝, a 和 b 完全拷贝了父对象及其子对象,两者是完全独立的。 更多实例 以下实例是使用 copy 模块的 copy.copy( 浅拷贝 )和(copy.deepcopy ): 实例 #!/usr/bin/python # -*-coding:utf-8 -*- import copy a = [1, 2, 3, 4, ['a', 'b']] #原始对象 b = a #赋值,传对象的引用 c = copy.copy(a) #对象拷贝,浅拷贝 d = copy.deepcopy(a) #对象拷贝,深拷贝 a.append(5) #修改对象a a[4].append('c') #修改对象a中的['a', 'b']数组对象 print( 'a = ', a ) print( 'b = ', b ) print( 'c = ', c ) print( 'd = ', d ) 以上实例执行输出结果为: ('a = ', [1, 2, 3, 4, ['a', 'b', 'c'], 5]) ('b = ', [1, 2, 3, 4, ['a', 'b', 'c'], 5]) ('c = ', [1, 2, 3, 4, ['a', 'b', 'c']]) ('d = ', [1, 2, 3, 4, ['a', 'b']])
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2.问题总结
1. alias取别名
利用alias取别名时,=之间不要有空格。
如:
2. 在firefly电脑上运行无人机项目
source devel/setup.sh
3.使用tqdm可以动态显示训练的进度条
4.在终端输入
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查看cpu使用情况5.python进行赋值时,尤其是为了保存上一状态时,注意深拷贝浅拷贝的区别,否则有可能值是一样的。
The text was updated successfully, but these errors were encountered: