Python for Data Analysts
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Find top Python resources from global universities, cool projects, and learning materials for data analytics.

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Your first SQL script will confuse even yourself.

Your first Power BI dashboard will look like it's your first dashboard.

Stop trying to perfect your first handful of projects.

Start pumping out projects left and right.

While learning, it's more important to create than to focus on optimizing.

Quantity > Quality

Once you start getting faster, you'll have more time to swap it to.

Quality > Quantity

You'll improve rapidly this way.
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Essential Pandas Functions for Data Analysis

Data Loading:

pd.read_csv() - Load data from a CSV file.

pd.read_excel() - Load data from an Excel file.


Data Inspection:

df.head(n) - View the first n rows.

df.info() - Get a summary of the dataset.

df.describe() - Generate summary statistics.


Data Manipulation:

df.drop(columns=['col1', 'col2']) - Remove specific columns.

df.rename(columns={'old_name': 'new_name'}) - Rename columns.

df['col'] = df['col'].apply(func) - Apply a function to a column.


Filtering and Sorting:

df[df['col'] > value] - Filter rows based on a condition.

df.sort_values(by='col', ascending=True) - Sort rows by a column.


Aggregation:

df.groupby('col').sum() - Group data and compute the sum.

df['col'].value_counts() - Count unique values in a column.


Merging and Joining:

pd.merge(df1, df2, on='key') - Merge two DataFrames.

pd.concat([df1, df2]) - Concatenate

Here you can find essential Python Interview Resources๐Ÿ‘‡
https://whatsapp.com/channel/0029VaGgzAk72WTmQFERKh02

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๐ˆ๐ฆ๐ฉ๐จ๐ซ๐ญ๐ข๐ง๐  ๐๐ž๐œ๐ž๐ฌ๐ฌ๐š๐ซ๐ฒ ๐‹๐ข๐›๐ซ๐š๐ซ๐ข๐ž๐ฌ:

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
import seaborn as sns

๐‹๐จ๐š๐๐ข๐ง๐  ๐ญ๐ก๐ž ๐ƒ๐š๐ญ๐š๐ฌ๐ž๐ญ:

df = pd.read_csv('your_dataset.csv')

๐ˆ๐ง๐ข๐ญ๐ข๐š๐ฅ ๐ƒ๐š๐ญ๐š ๐ˆ๐ง๐ฌ๐ฉ๐ž๐œ๐ญ๐ข๐จ๐ง:

1- View the first few rows:
df.head()

2- Summary of the dataset:
df.info()

3- Statistical summary:
df.describe()

๐‡๐š๐ง๐๐ฅ๐ข๐ง๐  ๐Œ๐ข๐ฌ๐ฌ๐ข๐ง๐  ๐•๐š๐ฅ๐ฎ๐ž๐ฌ:

1- Identify missing values:
df.isnull().sum()

2- Visualize missing values:
sns.heatmap(df.isnull(), cbar=False, cmap='viridis')
plt.show()

๐ƒ๐š๐ญ๐š ๐•๐ข๐ฌ๐ฎ๐š๐ฅ๐ข๐ณ๐š๐ญ๐ข๐จ๐ง:

1- Histograms:
df.hist(bins=30, figsize=(20, 15))
plt.show()

2 - Box plots:
plt.figure(figsize=(10, 6))
sns.boxplot(data=df)
plt.xticks(rotation=90)
plt.show()

3- Pair plots:
sns.pairplot(df)
plt.show()

4- Correlation matrix and heatmap:
correlation_matrix = df.corr()
plt.figure(figsize=(12, 8))
sns.heatmap(correlation_matrix, annot=True, cmap='coolwarm')
plt.show()

๐‚๐š๐ญ๐ž๐ ๐จ๐ซ๐ข๐œ๐š๐ฅ ๐ƒ๐š๐ญ๐š ๐€๐ง๐š๐ฅ๐ฒ๐ฌ๐ข๐ฌ:
Count plots for categorical features:

plt.figure(figsize=(10, 6))
sns.countplot(x='categorical_column', data=df)
plt.show()

Python Interview Q&A: https://topmate.io/coding/898340

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ENJOY LEARNING ๐Ÿ‘๐Ÿ‘
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Forwarded from Python for Data Analysts
Python is a popular programming language in the field of data analysis due to its versatility, ease of use, and extensive libraries for data manipulation, visualization, and analysis. Here are some key Python skills that are important for data analysts:

1. Basic Python Programming: Understanding basic Python syntax, data types, control structures, functions, and object-oriented programming concepts is essential for data analysis in Python.

2. NumPy: NumPy is a fundamental package for scientific computing in Python. It provides support for large multidimensional arrays and matrices, along with a collection of mathematical functions to operate on these arrays.

3. Pandas: Pandas is a powerful library for data manipulation and analysis in Python. It provides data structures like DataFrames and Series that make it easy to work with structured data and perform tasks such as filtering, grouping, joining, and reshaping data.

4. Matplotlib and Seaborn: Matplotlib is a versatile library for creating static, interactive, and animated visualizations in Python. Seaborn is built on top of Matplotlib and provides a higher-level interface for creating attractive statistical graphics.

5. Scikit-learn: Scikit-learn is a popular machine learning library in Python that provides tools for building predictive models, performing clustering and classification tasks, and evaluating model performance.

6. Jupyter Notebooks: Jupyter Notebooks are an interactive computing environment that allows you to create and share documents containing live code, equations, visualizations, and narrative text. They are commonly used by data analysts for exploratory data analysis and sharing insights.

7. SQLAlchemy: SQLAlchemy is a Python SQL toolkit and Object-Relational Mapping (ORM) library that provides a high-level interface for interacting with relational databases using Python.

8. Regular Expressions: Regular expressions (regex) are powerful tools for pattern matching and text processing in Python. They are useful for extracting specific information from text data or performing data cleaning tasks.

9. Data Visualization Libraries: In addition to Matplotlib and Seaborn, data analysts may also use other visualization libraries like Plotly, Bokeh, or Altair to create interactive visualizations in Python.

10. Web Scraping: Knowledge of web scraping techniques using libraries like BeautifulSoup or Scrapy can be useful for collecting data from websites for analysis.

By mastering these Python skills and applying them to real-world data analysis projects, you can enhance your proficiency as a data analyst and unlock new opportunities in the field.

#Python
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Frequently asked Python practice questions and answers in Data Analyst Interview:
1.Temperature Conversion: Write a program that converts a given temperature from Celsius to Fahrenheit or from Fahrenheit to Celsius based on user input.
temp = float(input('Enter the temperature: '))
unit = input('Enter the unit (C/F): ').upper()
if unit == 'C':
converted = (temp * 9/5) + 32
print(f'Temperature in Fahrenheit: {converted}')
elif unit == 'F':
converted = (temp - 32) * 5/9
print(f'Temperature in Celsius: {converted}')
else:
print('Invalid unit')

2.Multiplication Table: Write a program that prints the multiplication table of a given number using a while loop.
num = int(input('Enter a number: '))
i = 1
while i <= 10:
print(f'{num} x {i} = {num * i}')
i += 1

3.Greatest of Three Numbers: Write a program that takes three numbers as input and prints the greatest of the three.
num1 = float(input('Enter first number: '))
num2 = float(input('Enter second number: '))
num3 = float(input('Enter third number: '))
if num1 >= num2 and num1 >= num3:
print(f'The greatest number is {num1}')
elif num2 >= num1 and num2 >= num3:
print(f'The greatest number is {num2}')
else:
print(f'The greatest number is {num3}')

4.Sum of Even Numbers: Write a program that calculates the sum of all even numbers between 1 and a given number using a while loop.
num = int(input('Enter a number: '))
total = 0
i = 2
while i <= num:
total += i
i += 2
print(f'The sum of even numbers up to {num} is {total}')

5.Check Armstrong Number: Write a program that checks if a given number is an Armstrong number.
num = int(input('Enter a number: '))
sum_of_digits = 0
original_num = num
while num > 0:
digit = num % 10
sum_of_digits += digit ** 3
num //= 10
if sum_of_digits == original_num:
print(f'{original_num} is an Armstrong number')
else:
print(f'{original_num} is not an Armstrong number')

6.Reverse a Number: Write a program that reverses the digits of a given number using a while loop.
num = int(input('Enter a number: '))
reversed_num = 0
while num > 0:
digit = num % 10
reversed_num = reversed_num * 10 + digit
num //= 10
print(f'The reversed number is {reversed_num}')

7.Count Vowels and Consonants: Write a program that counts the number of vowels and consonants in a given string.
string = input('Enter a string: ').lower()
vowels = 'aeiou'
vowel_count = 0
consonant_count = 0
for char in string:
if char.isalpha():
if char in vowels:
vowel_count += 1
else:
consonant_count += 1
print(f'Number of vowels: {vowel_count}')
print(f'Number of consonants: {consonant_count}')

Python Interview Q&A: https://topmate.io/coding/898340

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ENJOY LEARNING ๐Ÿ‘๐Ÿ‘
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๐Ÿ” Machine Learning Cheat Sheet ๐Ÿ”

1. Key Concepts:
- Supervised Learning: Learn from labeled data (e.g., classification, regression).
- Unsupervised Learning: Discover patterns in unlabeled data (e.g., clustering, dimensionality reduction).
- Reinforcement Learning: Learn by interacting with an environment to maximize reward.

2. Common Algorithms:
- Linear Regression: Predict continuous values.
- Logistic Regression: Binary classification.
- Decision Trees: Simple, interpretable model for classification and regression.
- Random Forests: Ensemble method for improved accuracy.
- Support Vector Machines: Effective for high-dimensional spaces.
- K-Nearest Neighbors: Instance-based learning for classification/regression.
- K-Means: Clustering algorithm.
- Principal Component Analysis(PCA)

3. Performance Metrics:
- Classification: Accuracy, Precision, Recall, F1-Score, ROC-AUC.
- Regression: Mean Absolute Error (MAE), Mean Squared Error (MSE), R^2 Score.

4. Data Preprocessing:
- Normalization: Scale features to a standard range.
- Standardization: Transform features to have zero mean and unit variance.
- Imputation: Handle missing data.
- Encoding: Convert categorical data into numerical format.

5. Model Evaluation:
- Cross-Validation: Ensure model generalization.
- Train-Test Split: Divide data to evaluate model performance.

6. Libraries:
- Python: Scikit-Learn, TensorFlow, Keras, PyTorch, Pandas, Numpy, Matplotlib.
- R: caret, randomForest, e1071, ggplot2.

7. Tips for Success:
- Feature Engineering: Enhance data quality and relevance.
- Hyperparameter Tuning: Optimize model parameters (Grid Search, Random Search).
- Model Interpretability: Use tools like SHAP and LIME.
- Continuous Learning: Stay updated with the latest research and trends.

๐Ÿš€ Dive into Machine Learning and transform data into insights! ๐Ÿš€

Best Data Science & Machine Learning Resources: https://topmate.io/coding/914624

All the best ๐Ÿ‘๐Ÿ‘
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SQL Joins โœ…
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A step-by-step guide to land a job as a data analyst

Landing your first data analyst job is toughhhhh.

Here are 11 tips to make it easier:

- Master SQL.
- Next, learn a BI tool.
- Drink lots of tea or coffee.
- Tackle relevant data projects.
- Create a relevant data portfolio.
- Focus on actionable data insights.
- Remember imposter syndrome is normal.
- Find ways to prove youโ€™re a problem-solver.
- Develop compelling data visualization stories.
- Engage with LinkedIn posts from fellow analysts.
- Illustrate your analytical impact with metrics & KPIs.
- Share your career story & insights via LinkedIn posts.

I have curated best 80+ top-notch Data Analytics Resources ๐Ÿ‘‡๐Ÿ‘‡
https://whatsapp.com/channel/0029VaGgzAk72WTmQFERKh02

Hope this helps you ๐Ÿ˜Š
๐Ÿ‘2โค1๐Ÿ‘1
Commonly used Python functions and methods:

### STRING FUNCTIONS:
- len(): Returns the length of a string.
- str.upper(): Converts a string to upper-case.
- str.lower(): Converts a string to lower-case.
- str.capitalize(): Capitalizes the first character of a string.
- str.split(): Splits a string into a list.
- str.join(): Joins elements of a list into a string.
- str.replace(): Replaces a specified phrase with another specified phrase.
- str.strip(): Removes whitespace from the beginning and end of a string.

### LIST FUNCTIONS:
- len(): Returns the length of a list.
- list.append(): Adds an item to the end of the list.
- list.extend(): Adds the elements of a list (or any iterable) to the end of the current list.
- list.insert(): Adds an item at a specified position.
- list.remove(): Removes the first item with the specified value.
- list.pop(): Removes the item at the specified position.
- list.index(): Returns the index of the first element with the specified value.
- list.sort(): Sorts the list.
- list.reverse(): Reverses the order of the list.

### DICTIONARY FUNCTIONS:
- dict.keys(): Returns a list of all the keys in the dictionary.
- dict.values(): Returns a list of all the values in the dictionary.
- dict.items(): Returns a list of tuples, each tuple containing a key and a value.
- dict.get(): Returns the value of the specified key.
- dict.update(): Updates the dictionary with the specified key-value pairs.
- dict.pop(): Removes the element with the specified key.

### TUPLE FUNCTIONS:
- len(): Returns the length of a tuple.
- tuple.count(): Returns the number of times a specified value appears in a tuple.
- tuple.index(): Searches the tuple for a specified value and returns the position of where it was found.

### SET FUNCTIONS:
- len(): Returns the length of a set.
- set.add(): Adds an element to the set.
- set.remove(): Removes the specified element.
- set.union(): Returns a set containing the union of sets.
- set.intersection(): Returns a set containing the intersection of sets.
- set.difference(): Returns a set containing the difference of sets.
- set.symmetric_difference(): Returns a set with elements in either the set or the specified set, but not both.

### NUMERIC FUNCTIONS:
- abs(): Returns the absolute value of a number.
- round(): Rounds a number to a specified number of digits.
- max(): Returns the largest item in an iterable.
- min(): Returns the smallest item in an iterable.
- sum(): Sums the items of an iterable.

### DATE AND TIME FUNCTIONS (datetime module):
- datetime.datetime.now(): Returns the current date and time.
- datetime.datetime.today(): Returns the current local date.
- datetime.datetime.strftime(): Formats a datetime object as a string.
- datetime.datetime.strptime(): Parses a string to a datetime object.

### FILE I/O FUNCTIONS:
- open(): Opens a file and returns a file object.
- file.read(): Reads the contents of a file.
- file.write(): Writes data to a file.
- file.readlines(): Reads all the lines of a file into a list.
- file.close(): Closes the file.

### GENERAL FUNCTIONS:
- print(): Prints to the console.
- input(): Reads a string from standard input.
- type(): Returns the type of an object.
- isinstance(): Checks if an object is an instance of a class or a tuple of classes.
- id(): Returns the identity of an object.

Here you can find essential Python Interview Resources๐Ÿ‘‡
https://whatsapp.com/channel/0029VaGgzAk72WTmQFERKh02

Like this post for more resources like this ๐Ÿ‘โ™ฅ๏ธ

Share with credits: https://t.iss.one/sqlspecialist

Hope it helps :)
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Many people ask this common question โ€œCan I get a job with just SQL and Excel?โ€ or โ€œCan I get a job with just Power BI and Python?โ€.

The answer to all of those questions is yes.

There are jobs that use only SQL, Tableau, Power BI, Excel, Python, or R or some combination of those.

However, the combination of tools you learn impacts the total number of jobs you are qualified for.

For example, letโ€™s say with just SQL and Excel you are qualified for 10 jobs, but if you add Tableau to that, you are qualified for 50 jobs.

If you have a success rate of landing a job youโ€™re qualified for of 4%, having 5 times as many jobs to go for greatly improves your odds of landing a job.

Does this mean you should go out there and learn every single skill any data analyst job requires?

NO!

Itโ€™s about finding the core tools that many jobs want.

And, in my opinion, those tools are SQL, Excel, and a visualization tool.

With these three tools, you are qualified for the majority of entry level data jobs and many higher level jobs.

So, you can land a job with whatever tools youโ€™re comfortable with.

But if you have the three tools above in your toolbelt, you will have many more jobs to apply for and greatly improve your chances of snagging one.
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Top 5 Case Studies for Data Analytics: You Must Know Before Attending an Interview

1. Retail: Target's Predictive Analytics for Customer Behavior
Company: Target
Challenge: Target wanted to identify customers who were expecting a baby to send them personalized promotions.
Solution:
Target used predictive analytics to analyze customers' purchase history and identify patterns that indicated pregnancy.
They tracked purchases of items like unscented lotion, vitamins, and cotton balls.
Outcome:
The algorithm successfully identified pregnant customers, enabling Target to send them relevant promotions.
This personalized marketing strategy increased sales and customer loyalty.

2. Healthcare: IBM Watson's Oncology Treatment Recommendations
Company: IBM Watson
Challenge: Oncologists needed support in identifying the best treatment options for cancer patients.
Solution:
IBM Watson analyzed vast amounts of medical data, including patient records, clinical trials, and medical literature.
It provided oncologists with evidencebased treatment recommendations tailored to individual patients.
Outcome:
Improved treatment accuracy and personalized care for cancer patients.
Reduced time for doctors to develop treatment plans, allowing them to focus more on patient care.

3. Finance: JP Morgan Chase's Fraud Detection System
Company: JP Morgan Chase
Challenge: The bank needed to detect and prevent fraudulent transactions in realtime.
Solution:
Implemented advanced machine learning algorithms to analyze transaction patterns and detect anomalies.
The system flagged suspicious transactions for further investigation.
Outcome:
Significantly reduced fraudulent activities.
Enhanced customer trust and satisfaction due to improved security measures.

4. Sports: Oakland Athletics' Use of Sabermetrics
Team: Oakland Athletics (Moneyball)
Challenge: Compete with larger teams with higher budgets by optimizing player performance and team strategy.
Solution:
Used sabermetrics, a form of advanced statistical analysis, to evaluate player performance and potential.
Focused on undervalued players with high onbase percentages and other key metrics.
Outcome:
Achieved remarkable success with a limited budget.
Revolutionized the approach to team building and player evaluation in baseball and other sports.

5. Ecommerce: Amazon's Recommendation Engine
Company: Amazon
Challenge: Enhance customer shopping experience and increase sales through personalized recommendations.
Solution:
Implemented a recommendation engine using collaborative filtering, which analyzes user behavior and purchase history.
The system suggests products based on what similar users have bought.
Outcome:
Increased average order value and customer retention.
Significantly contributed to Amazon's revenue growth through crossselling and upselling.

Like if it helps ๐Ÿ˜„
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How to revolutionize Hollywood with AI.

Unlock new possibilities:

1. Voice Cloning

Clone voices of Hollywood icons:

โ€ข Legally clone and use voices with permission.
โ€ข Recreate iconic voices for new projects.
โ€ข Preserve legendary performances for future generations.

2. Custom Voices

Create unique voices for your projects:

โ€ข Generate up to 20 seconds of dialogue.
โ€ข Select from preset voice options or create your own.

3. Lip Sync Tool

Bring still characters to life:

โ€ข Use ElevenLabs's Lip Sync tool.
โ€ข Select a face and add a script.
โ€ข Generate videos with synchronized lip movements.

AI is reshaping the industry, voice cloning is part of a broader trend.

Filmmakers can now recreate voices of iconic actors.
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