break the loop when list len reaches to 5 (In for loop)

user_19914628 0
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I am building a simple python program and I am trying to filter some response based on limit to run the for loop or while loop.

What I am trying to do ?

I am trying to stop the loop when list len reaches to 5. It can be a for loop and while loop.

views.py

def filter_array(request):
   new_array = []
   count = 1
   quit = False
   
   for m in res.get("blogs"):
      for likes in m.get("likes"):
         try:
             count += 1
             if likes == "user_1":
                 new_array.append(likes)

             if count == 5:
                 quit = True
                 break
         except:
                 quit = True
                 break
   print(new_array)

   return new_array

json response in views.py

res = {
   "blogs": [
      {
         "title": "Blog 1",
         "description": "Blog description",
         "likes": [
            "user_1",
            "user_2",
         ]
      },
      {
         "title": "Blog 2",
         "description": "Blog description",
         "likes": [
            "user_4",
            "user_5",
         ]
      },
      {
         "title": "Blog 3",
         "description": "Blog description",
         "likes": [
            "user_3",
         ]
      },
      {
         "title": "Blog 4",
         "description": "Blog description",
         "likes": [
            "user_3",
            "user_4",
            "user_5",
         ]
      },
      {
         "title": "Blog 5",
         "description": "Blog description",
         "likes": [
            "user_4",
            "user_5",
         ]
      },
   ]
}

When I run the above code then It is appending all the json items in the array. But I want to append in list if "likes" is user_1 and stop loop when list len reaches the 5.

I have tried many hours but it is still not working.

Any help would be much Appreciated.

list django arrays python json
4 Answers

I am not sure what you are trying to do exactly, but from what I understand, try this:

def filter_array(request):
    new_array = []
    count = 1
    flag = False
    for m in res.get("blogs"):
        for likes in m.get("likes"):
            try:
                count += 1
                if likes == "user_1":
                    new_array.append(likes)

                if count == 5:
                    flag = True
                    break
            except:
                flag = True
                break
        if flag: # break if flag is True
            break
    print(new_array)
    return new_array

Changes

  1. Use flag instead of quit because quit() is a built-in function.
  2. Added flag check in outer for-loop.
user_142578860

The break only breaks out of one loop. Because you have a 2nd loop nested inside of the 1st loop you need another break.

def filter_array(request):
   new_array = []
   count = 1
   
   for m in res.get("blogs"):
      for likes in m.get("likes"):
         count += 1
         if likes == "user_1":
            new_array.append(likes)
            
         if count == 5:
            break
      if count == 5:
         break
   print(new_array)
   
   return new_array
user_197610370

IIUC this is all you need:

res = {
    "blogs": [
      {
          "title": "Blog 1",
          "description": "Blog description",
          "likes": [
              "user_1",
              "user_2",
          ]
      },
        {
          "title": "Blog 2",
          "description": "Blog description",
          "likes": [
              "user_4",
              "user_5",
          ]
      },
        {
          "title": "Blog 3",
          "description": "Blog description",
          "likes": [
              "user_3",
          ]
      },
        {
          "title": "Blog 4",
          "description": "Blog description",
          "likes": [
              "user_3",
              "user_4",
              "user_5",
          ]
      },
        {
          "title": "Blog 5",
          "description": "Blog description",
          "likes": [
              "user_4",
              "user_5",
          ]
      },
    ]
}

new_list = []

for dict_ in res['blogs']:
    if 'user_1' in dict_.get('likes', []):
        new_list.append(dict_)
        if len(new_list) == 5:
            break

print(new_list)

Output:

[{'title': 'Blog 1', 'description': 'Blog description', 'likes': ['user_1', 'user_2']}]
user_175803810

You can get the first five elements of a list with a slice. Something like this:

def filter_array(request):
    all_likes = []
    for likes in m.get("likes", [])
        all_likes.extend(likes)
    return all_likes[:5]

Don't make things more complicated than you need to. For example, there is no reason for a try...except here.

user_14405650
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