Explore puzzles designed to enhance your critical thinking and problem-solving skills using pandas. Gain insights into common pitfalls and sharpen your data manipulation techniques.

test.tar.gz

test

test2

Puzzles are a great way to practice your critical thinking and problem-solving skills. This course assumes a basic understanding of pandas.  The teasers and puzzles in this course are designed to help you practice what you already know and help avoid future mistakes.

Pandas Brain Teasers

# Try it yourself
Try executing the code below to see the result.

import pandas as pd

grades = pd.Series([61, 82, 57])
bonuses = pd.Series([10, 5, 10, 10])
out = grades + bonuses
print(out)

# Explanation
The `pandas.Series` and `numpy.ndarray` are different from Python lists. The `+` operator included on Python lists does concatenation:
```py
In [1]: [1, 2, 3] + [4, 5]
Out[1]: [1, 2, 3, 4, 5]
```

The `numpy.ndarray` and `pandas.Series` that is built on it, have different behavior. They'll do element-wise operations and try to match the dimensions as much as possible, which is a process known as **broadcasting**.
```py
In [2]: np.array([1,2,3]) + np.array([4,5,6])
Out[2]: array([5, 7, 9])
In [3]: np.array([1,2,3]) + 3
Out[3]: array([4, 5, 6])
```
If NumPy can't broadcast, it'll raise an error like the one below:
```
In [4]: np.array([1,2,3]) + np.array([4,5,6,7])
...
ValueError: operands could not be broadcast together with shapes (3,) (4,)
```
This is where pandas diverges from NumPy. The `pandas.Series` (and `pandas.DataFrame`)
uses labels for matching elements somewhat like a SQL join.
```
In [5]: s1 = pd.Series([1,2,3], index=['a', 'b', 'c'])
In [6]: s2 = pd.Series([10,20,30], index=['c', 'b', 'a'])
In [7]: s1 + s2
Out[7]:
a 31
b 22
c 13
dtype: int64
```
When pandas can't find a matching label, it'll use `nan` for a value, which is what happens in this teaser.

Let's learn how to add the values of two pandas series.

Before We Begin

Puzzles

Wrapping Up

Add the Values of a Pandas Series

Try it yourself

Explanation