joeyajames / python

Python code for YouTube videos.

joeyajames

homepage at https://joeyajames.github.io

python's Issues

What if i want to find the height of the BST ?

Is this the right approach ?

class node:
    def getHeight(self):
        if self is None:
            return -1
        return 1 + max(self.leftChild.getHeight(), self.rightChild.getHeight())

class Tree:
    def getHeight(self):
        if self.root:
            return self.root.getHeight()
        else:
            return -1

keys function is returning first pair for each hash instead of all keys

Python/HashMap.py

Line 52 in ba3e6e6

arr.append(self.map[i][0])

It is going to each hash location, checking if pairs exist and returning the 0th pairs.

It needs to go to each hash location, check if pairs exist and loop over each pair and return their 0th element i.e. the keys.

check length if list of index to avoid index out of bound error

Python/MaxHeap.py

Line 18 in ba3e6e6

if self.heap[1]:

It is directly checked as if lst[1].
This will give error if index does not exist in lst.
Instead, we need to check if len(lst) >= 2 i.e. whether 1st element exists or not.

i cant find the bfs and dfs code

NameError: name 'threshold' is not defined

Python/Sorting Algorithms/quick_sort.py

Line 8 in ba3e6e6

if hi-low < threshold and low < hi:

Either threshold related condition should be removed or threshold should be defined somewhere.

NameError: name 'threshold' is not defined

Python/Sorting Algorithms/quick_sort.py

Line 8 in 5cdfb6d

if hi-low < threshold and low < hi:

[bug] : Time series analysis

pandas_weather.py #11 produces an error

The reason for the error is that the key 'avg_high' can't be found because it has been changed to 'av_hi'.

Here is the link to the file:
https://github.com/joeyajames/Python/blob/master/Pandas/pandas_weather.py

Here is the output:

--------------------------------------------------
[ 11. iterate rows of df with a for loop ]

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
~/opt/anaconda3/lib/python3.7/site-packages/pandas/core/indexes/base.py in get_value(self, series, key)
   4409             try:
-> 4410                 return libindex.get_value_at(s, key)
   4411             except IndexError:

pandas/_libs/index.pyx in pandas._libs.index.get_value_at()

pandas/_libs/index.pyx in pandas._libs.index.get_value_at()

pandas/_libs/util.pxd in pandas._libs.util.get_value_at()

pandas/_libs/util.pxd in pandas._libs.util.validate_indexer()

TypeError: 'str' object cannot be interpreted as an integer

During handling of the above exception, another exception occurred:

KeyError                                  Traceback (most recent call last)
<ipython-input-14-1fc7b7226e62> in <module>
      2 header("11. iterate rows of df with a for loop")
      3 for index, row in df.iterrows():
----> 4     print (index, row["month"], row["avg_high"])

~/opt/anaconda3/lib/python3.7/site-packages/pandas/core/series.py in __getitem__(self, key)
    869         key = com.apply_if_callable(key, self)
    870         try:
--> 871             result = self.index.get_value(self, key)
    872 
    873             if not is_scalar(result):

~/opt/anaconda3/lib/python3.7/site-packages/pandas/core/indexes/base.py in get_value(self, series, key)
   4416                     raise InvalidIndexError(key)
   4417                 else:
-> 4418                     raise e1
   4419             except Exception:
   4420                 raise e1

~/opt/anaconda3/lib/python3.7/site-packages/pandas/core/indexes/base.py in get_value(self, series, key)
   4402         k = self._convert_scalar_indexer(k, kind="getitem")
   4403         try:
-> 4404             return self._engine.get_value(s, k, tz=getattr(series.dtype, "tz", None))
   4405         except KeyError as e1:
   4406             if len(self) > 0 and (self.holds_integer() or self.is_boolean()):

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_value()

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_value()

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

KeyError: 'avg_high'

Can you consider change the code of "graph_adjacency-matrix.py" a little?

Can you consider change the position of
self.edges.append([0] * (len(self.edges)+1))
after this line
self.vertices[vertex.name] = vertex

Since
self.edges.append([0] * (len(self.edges)+1))
is for initializing the matrix to zeros. Especially, adding the first edge, it is not easy to understand. Because when this line changes position it follows the initializing, appending new initialized edges, fill the weight number logic. That will be more easy for comprehension.

Updation in TempConversation.py

Function and Variable Naming: Changed function names and variable names to follow Python's naming conventions (snake_case).

Input Parsing: Changed eval to float for parsing input to ensure safer evaluation of user input.

Output Formatting: Used f-strings for cleaner and more readable output formatting.

Choice Comparison: Changed the comparison to strings ('1', '2', '3') instead of integers to match the input type.

Exit Condition: Changed the exit condition to compare the choice with a string '3' instead of an integer 3.

Main Guard: Added if name == "main": guard to ensure that main() function is executed only when the script is run directly, not when it's imported elsewhere. This is a common best practice in Python.

Delay in bulk file transfer from one USB drive to another USB drive

Hi,

I am experiencing delay in transferring files from one USB drive to another USB drive using python code.
Initially transferring of files from the USB drive takes place very fast and gradually slow down to 10 kbps.

Is there any way to slowing down the file transfer process.

My python code is given below

import os
import shutil
directory = "name of the new directory"
dir_create = "Path of the destination directory" #destination directory
path = os.path.join(dir_create, directory)
os.mkdir(path) # create a new directory
dir_dst = "Path of the new destination directory"
dir_src = "Path of the Source directory" # .csv data file source directory
for filename in os.listdir(dir_src):
if filename.endswith('.csv'):
shutil.copy(dir_src + filename, dir_dst)

de

Hi,

I am starting to get in touch with linked lists and other data structures types,
A part ";" errors I found in the code, the problem is in the newlist [type List] there will be references of objects "nodes" of previous linked lists and not the "data", so I propose to you to use get_data() function when appending data to the temporary list instead of node object references which will simplify the code as below:

def sort_list(self, reverse_list = True):
if self.size > 1:
temp_list = []
current = self.root

            temp_list.append(current.get_data())
            while current.has_next_node():
                current = current.get_next()
                temp_list.append(current.get_data())
            
            temp_list = sorted(temp_list,  reverse = reverse_list)
            
            sorted_Linked_List = LinkedList()
            for element in temp_list:
                sorted_Linked_List.add_node(element)
            return sorted_Linked_List
        return self

suggestions

@joeyajames i want to add some new snippets on OOPs

About the time complexity

Thank you very much for your video and code!

But I actually have one question about your codes time complexity. The following two lines of codes showing that you are using Python slicing to construct the left half and right half:

L = A[first:middle+1]
R = A[middle+1:last+1]

Since the slicing operator is O(k), my question is does the time complexity of the merge sort still be O(nlogn) if we use the Python list slicing in our codes?

Thank you very much!

Python-OOP concepts

Presentation about OOP concepts is very short and incomplete for someone who wants to learn it.

api exchange rates

Thanks for your notebook and YT video's. Now a days I believe you need a key for accessing the api. Maybe use another website as example

Module not found error in code of matplotlib and pandas library

@joeyajames The code of matplotlib library as well as pandas library is not executing since there is a typo mistake in code . Please assign me this issue .

trouble calling the list

Hello,
How can I call the added list (created list)?

Initial size needs to be as per the size of root i.e. 0 or 1 or n(if applicable)

Python/LinkedLists/LinkedList0.py

Line 24 in ba3e6e6

self.size = 0

User is given flexibility to either create linked list with root as None or with a root node given by them.
i.e. size could be 0 or 1

If applicable:
User can also pass root that already has more next nodes.
i.e. size could be n

But, initial size is always set as 0 instead of calculating and setting it as per above logic

Temperature conversion project

In this project, if the user inputs a text with alpabetic characters as the choice variable, it gives an error. Even if the choice is 1 or 2, if the user inputs a alphabetic string, it gives an error as well. So, we need to check the user's answer and respond accordingly, so that it doesn't give an error.

This repo doesn't have contributing file.

I am making one text file for contributing file for those who intend to contribute to this repository.

turtle_graphics.py updation needed .

Choice Function: Replaced sample with choice for selecting a single random item from a sequence. This simplifies the code when only one random choice is needed.

Pen State Functions: Corrected the function names from pu and pd to penup and pendown, respectively, for clarity and consistency.

Position Copy: Used the copy() method to create a copy of the position vector before modifying it. This prevents unintended changes to the original position vector.

Distance Calculation: Replaced abs(tt.pos() - start_position) with tt.distance(start_position) to calculate the distance between two points more accurately.

Indentation and Formatting: Ensured consistent indentation and formatting throughout the code for readability and maintainability.

de

Hi,

I am starting to get in touch with linked lists and other data structures types,
A part ";" errors I found in the code, the problem is in the newlist [type List] there will be references of objects "nodes" of previous linked lists and not the "data", so I propose to you to use get_data() function which will simplify the code as:

def sort_list(self, reverse_list = True):
if self.size > 1:
temp_list = []
current = self.root

            temp_list.append(current.get_data())
            while current.has_next_node():
                current = current.get_next()
                temp_list.append(current.get_data())
            
            temp_list = sorted(temp_list,  reverse = reverse_list)
            
            sorted_Linked_List = LinkedList()
            for element in temp_list:
                sorted_Linked_List.add_node(element)
            return sorted_Linked_List
        return self

Suggestions

In Sorting Algorithms/quick_sort.py Please consider changing arguments names to meet the snake case rolls and also do not use names like A due to the Shadows name 'A' from outer scope

Error while printing (high_temps)

high_temps = []
for row in rows:
tds = row.find_all('td')
for i in range(1,7):
high_temps.append(tds[i].text)
print(high_temps)

---

IndexError Traceback (most recent call last)
in ()
8 tds = row.find_all('td')
9 for i in range(1,7):
---> 10 high_temps.append(tds[i].text)
11 print(high_temps)

IndexError: list index out of range

instantiation

I'n not an expert but i would like to know if there wasn't better to type the init method like this:

class Shape:
def init(self, color=None):
if color == None:
self.color = ""
else:
self.color = color

since the input for color is expected to be a string type

gdsjgjds

Ut4py

de

Hi,

I am starting to get in touch with linked lists and other data structures types,
A part ";" errors I found in the code, the problem is in the newlist [type List] there will be references of objects "nodes" of previous linked lists and not the "data", so I propose to you to use get_data() function which will simplify the code as:

def sort_list(self, reverse_list = True):
if self.size > 1:
temp_list = []
current = self.root

            temp_list.append(current.get_data())
            while current.has_next_node():
                current = current.get_next()
                temp_list.append(current.get_data())
            
            temp_list = sorted(temp_list,  reverse = reverse_list)
            
            sorted_Linked_List = LinkedList()
            for element in temp_list:
                sorted_Linked_List.add_node(element)
            return sorted_Linked_List
        return self

Bug: Need import json in the 'Python Requests' notebook

Updation in MaxHeap.py

Naming Conventions: Renamed private methods to follow Python's naming conventions (snake_case).

Returning None: Changed the return value of peek and pop methods to None instead of False for clarity. In Python, None is typically used to indicate the absence of a value.

Use of Dummy Element: Initialized the heap with a dummy element at index 0 to simplify index calculations. This helps in avoiding special cases in the code.

Output Formatting: Changed the output printing to exclude the dummy element when printing the heap elements.

Doubly Linked List - remove error

I don't believe the else statement self.root = this_node in the below remove function is correct. If there is no previous node, that means you are at the root; and the root should be set to next not this_node

    def remove (self, d):
        this_node = self.root

        while this_node:
            if this_node.get_data() == d:
                next = this_node.get_next()
                prev = this_node.get_prev()
                
                if next:
                    next.set_prev(prev)
                if prev:
                    prev.set_next(next)
                else:
                    self.root = this_node
                self.size -= 1
                return True		# data removed
            else:
                this_node = this_node.get_next()
        return False  # data not found