In [ ]:

```
from __future__ import division, print_function
```

Write a function called `invertBool(l)`

that takes in a list of lists called `l`

, and returns a list of lists that represents all the booleans in the matrix, inverted.

For example:

`invertBool(`

```
[[True, False, True],
[False, True, True],
[False, False, False]])
```

=>

```
[[False, True, False],
[True, False, False],
[True, True, True]]
```

In [11]:

```
# write code here
```

Run the following cell to test your `invertBool(l)`

function.

In [10]:

```
def test():
lsts = [[[True, False, True, True],
[False, False, False, True],
[True, True, True, True],
[False, True, False, True]],
[[False, True, False],
[True, True, True],
[False, False, False]]]
ans = [[[False, True, False, False],
[True, True, True, False],
[False, False, False, False],
[True, False, True, False]],
[[True, False, True],
[False, False, False],
[True, True, True]]]
for i in range(2):
if invertBool(lsts[i]) != ans[i]:
return "Test Failed :'("
return "All Tests Passed!"
test()
```

Out[10]:

Write a function called `diagProd(l)`

that takes in a list of integer or float lists where each nested list are the same length, and returns the product of a matrix's diagonal. You may assume the list is non-empty.

For example:

`diagProd(`

```
[[12, 5, 3],
[2, 1, 3],
[35, 23, 2]]
```

)

will return `24`

.

In [20]:

```
# Write your function here
```

Run the following cell to test your `diagProd(l)`

function.

In [21]:

```
def test():
lst = [
[[12, 5, 3],
[2, 1, 3],
[35, 23, 2]],
[[54, 345, 23, 25],
[135, 43, 3, 5],
[75, 46, 63, 15],
[16, 10, 9, 2]],
[[1]],
[[2, 4],
[4, 2]]
]
ans = [24,292572, 1, 4]
for i in range(2):
if diagProd(lst[i]) != ans[i]:
return "Test Failed :'("
return "All Tests Passed!"
test()
```

Out[21]:

Write a function called `symmetric(l)`

that takes in a list of integer lists called `l`

, and returns a boolean on whether or not the matrix is symmetric. Recall that a matrix is symmetric if and only if when the ith columm becomes the ith row, it is still the same matrix.

*Hint: You can do this without looking at the elements more than once.*

For example:

`symmetric(`

```
[[12, 5, 3],
[2, 1, 3],
[35, 23, 2]] )
```

will return `False`

.

`symmetric(`

```
[[1, 4, 5],
[4, 2, 6],
[5, 6, 3]] )
```

will return `True`

.

In [34]:

```
# Write your code here
```

Run the following cell to test your `symmetric(l)`

function.

In [33]:

```
def test():
lst = [[[12, 5, 3],
[2, 1, 3],
[35, 23, 2]],
[[1, 4, 5],
[4, 2, 6],
[5, 6, 3]],
[[2, 4],
[4, 2]],
[[54, 345, 23, 25],
[135, 43, 3, 5],
[75, 46, 63, 15],
[16, 10, 9, 2]]
]
ans = [False, True, True, False]
for i in range(4):
if symmetric(lst[i]) != ans[i]:
return f'Test Case #{i +1} Failed'
return "All Test Cases Passed!"
test()
```

Out[33]:

Write the function `advancedCheckered(x)`

that takes in an integer `s`

and prints a `s`

by `s`

checkerboard that has hashtags starting on even lines, and has percent signs starting on the odd lines, and they alternate during the line.

For example:

```
advancedCheckered(4) →
#%#%
%#%#
#%#%
%#%#
```

In [1]:

```
# Write code here
```

An image is usually represented as a 2D array, but let's say we only have access to a 1D array. Is there a way that we can represent a 2D array using a 1D array? Here's a picture that describes how we can store an image as a 1D array.

<img src = "2D.png" width = "800px"> <img src = "1D.png" width = "800px">

Write a function called `getPixel(lst, h, w, i, j)`

where `lst`

is a 1D array, `h`

is the height of the image, `w`

is the width of image, `i`

is the row that the pixel is on, and `j`

is the column that the pixel is on. Then, this function will return the value that the pixel holds.

Write a function called `1Dto2D`

that takes in a list of integer pixels `lst`

, height `h`

, and width `w`

and returns the 2D array representation of the image.

For example:

```
1Dto2D([34, 234, 23, 255, 98, 23, 155, 87], 2, 4) →
[[34, 234, 23, 255],
[98, 23, 155, 87]]
```