Question

我正在编写一个程序，该程序将为纽约摄影师提供摄影创意。现在它的工作方式非常简单，代码利用random.choice函数从列表中随机提取项目，然后代码以最终形成英语句子的方式打印出来。

我的问题是我需要为此添加一些逻辑，因为某些结果对于摄影师来说是没有意义的（至少在我看来）。在此示例中，我试图从technique_list中删除“ Bracketed（HDR）”，如果python选择主题项时随机选择了“ Portrait”，则为“ Portrait”。

我觉得我在条件if语句中误用了.remove函数。有一个更好的方法吗？我已附上代码的相关部分进行检查。

我尝试了technique_list.remove（'Bracketed（HDR）'）以及

del technique_list [0]，都作为if语句的响应部分。

import random 

print ("You should try taking a...")

#pool of items that the program will randomly choose..
theme_list = ['Cityscape','Peoplescape','Port-Scape', 'Portrait']
technique_list  = ['Bracketed (HDR)','Wide Angle', 'Zoom','Long 
Exposure','Fast Shutter','Daytime Long Expo','Timelapse']


#what we need here are conditional IF statements,  that manipulate items 
from various lists

#this bit of code determines the theme of a photo idea
theme_var = random.choice(theme_list) 
for theme in theme_var:
if theme == 'Portrait':
        technique_list.remove('Bracketed (HDR)') 
print("",theme_var)

#this bit of code determines the technique of a photo idea
technique_var = random.choice(technique_list)
print("", technique_var)

print("picture, from")

#this line of code determines the location of a photo idea
location_var = random.choice(location_list)
print("", location_var)

这仍然是代码的可能结果之一：

You should try taking a...
 Portrait
 Bracketed (HDR)
picture, from
 34th Street
during
 Sunrise
and then give it a
 Black & White
edit in Lightroom!
[Finished in 0.2

正如我之前说的，肖像和包围曝光（HDR）永远不应成为同一结果的一部分，对于这种情况没有意义。

Answer 1

问题（我认为）是因为您要遍历随机选择的结果而不是列表本身，所以不需要for循环。

theme_var = random.choice(theme_list) 

if theme_var == 'Portrait':
        technique_list.remove('Bracketed (HDR)') 
print("",theme_var)

#this bit of code determines the technique of a photo idea
technique_var = random.choice(technique_list)
print("", technique_var)

print("picture, from")

#rest of the code

应该这样做

Answer 2

我会使用一本不适当的技术字典，一个列表理解方法，并以f字符串开头：

import random 

#pool of items that the program will randomly choose..
theme_list = ['Cityscape','Peoplescape','Port-Scape', 'Portrait']
technique_list  = ['Bracketed (HDR)','Wide Angle', 'Zoom','Long Exposure','Fast 
Shutter','Daytime Long Expo','Timelapse']
location_list = ['34th Street']

# dictionary of inappropriate techniques for given theme
d_inappropes = {'Cityscape': [],
            'Port-Scape': [],
            'Portrait': ['Bracketed (HDR)'],
            'Peoplescape': ['Long Exposure', 'Timelapse', 'Daytime Long Expo']}

#this bit of code determines the theme of a photo idea
theme_var = random.choice(theme_list) 

#this bit of code determines the technique of a photo idea
# list comprehension generates a new list with the inappropriate techniques removed,
# without affecting the original list
technique_var = random.choice([ti for ti in technique_list if ti not in d_inappropes[theme_var]])

#this line of code determines the location of a photo idea
location_var = random.choice(location_list)

# use f-stirngs to put the whole output in a single line to keep it managable 
print(f"You should try taking a \n {theme_var} {technique_var} picture, \n from 
{location_var}.")

Answer 3

如果我可以添加答案并给出更多解释

如果选择了potrait，则要删除“括号（HDR）”。不要使用.remove，因为它将永久删除“括号（HDR）”并阻止其他主题使用该技术。您可以使用Kingfischer建议的不适当技术词典
random.choice从列表中输出了一个值。您不应该使用for循环，因为for循环会在random.choice
如果我可以提供反馈，那么您的代码片段中的缩进非常混乱。有些行应该有缩进，没有缩进。我不知道..也许是意料之外的，并且问题出在我的浏览器上。如果是这样，对不起！

有没有一种方法可以根据条件语句从各种列表中删除项目？

3 个答案: