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Question 1a

1. Create a (3,3) array where row 0 is [0, 0, 0], row 1 is [2, 2, 2], row 2 is [-2, -2, -2]. Print the array.
2. Change element [0,0] to 10 and element [2,2] to -10. Print the array.
3. Subtract 2 from every element. Print the array.
4. Print all of the elements of the revised array that are positive.
In [ ]: # Your codes for 1.
In [ ]: # Your codes for 2.
In [ ]: # Your codes for 3.
In [ ]: # Your codes for 4.
Question 1b
You are provided with two lists of numbers.
• List 'x' denotes all 8 possible dollar investment outcomes of a risky project;
• List 'p' denotes their corresponding outcome probabilities.
• For instance, there is a 5% chance of $10000.
In this question, let's first convert the two lists into two separate arrays. Can you use np.dot to calculate the expected value of this risky project? That is, 10000X0.05+1000X0.05+100X0.2 ... Calculation without using np.dot() will be considered no points.
Finally, print the following sentence using print+format: The expected value of this risky project is $XXX.X.
Hint: the portfolio mean return example at the end of 2.3
In [ ]: x = (10000, 1000, 100, 10, 1, 0, -10, -100]
p = [0.05, 0.05, 0.20, 0.20, 0.1, 0.1, 0.1, 0.2]
In [ ]: # Your code here

1 Answer

0 votes

Answer:

(1) The program in Python is as follows:

rows, cols = (3, 3)

arr =[[0,0,0],[2,2,2],[-2,-2,-2]]

print(arr)

arr[0][0] = 10

arr[2][2] = -10

print(arr)

for i in range(rows):

for j in range(cols):

arr[i][j]-=2

print(arr)

for i in range(rows):

for j in range(cols):

if arr[i][j]< 0:

print(arr[i][j], end = ", ")

(2) The program in Python is as follows:

import numpy as np

x = [10000, 1000, 100, 10, 1, 0, -10, -100]

p = [0.05, 0.05, 0.20, 0.20, 0.1, 0.1, 0.1, 0.2]

q = np.dot(x,p)

print(q)

Step-by-step explanation:

(1)

This initializes the rows and columns of the array to 3

rows, cols = (3, 3)

1. This creates and array and also populates it with the given data

arr =[[0,0,0],[2,2,2],[-2,-2,-2]]

Print the array

print(arr)

2. This changes index 0,0 to 10 and index 2,2 to -10

arr[0][0] = 10

arr[2][2] = -10

Print the array

print(arr)

This iterates through the rows and the columns of the array

for i in range(rows):

for j in range(cols):

3. This subtracts 2 from each array element

arr[i][j]-=2

Print the array

print(arr)

This iterates through the rows and the columns of the array

for i in range(rows):

for j in range(cols):

If array element is negative

if arr[i][j]< 0:

4. Print the array element

print(arr[i][j], end = ", ")

(2)

Line 1 and 2 are given as part of the program

x = [10000, 1000, 100, 10, 1, 0, -10, -100]

p = [0.05, 0.05, 0.20, 0.20, 0.1, 0.1, 0.1, 0.2]

This uses np dot to multiply x and p

q = np.dot(x,p)

This prints the result of the product

print(q)

User Alexzg
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