This page has 0 threads | Add post

Exercises

Finding our exercises useful? Please consider helping us to share more!

Software ==>	Python (34 exercises)
Topic ==>	Overview of NUMPY (2 exercises)
Level ==>	Average difficulty
Subject ==>	Python training

Use NumPy array functions to work out how much your pancake stall is spending on ingredients

This exercise is provided to allow potential course delegates to choose the correct Wise Owl Microsoft training course, and may not be reproduced in whole or in part in any format without the prior written consent of Wise Owl.

Before you can do this exercise, you'll need to download and unzip this file.

The above folder contains a spreadsheet analysing how many ingredients you buy for your modest pancake stall (Wise Owl are Crepe) in a typical week:

You have lots of supplies of cooking oil and salt in stock, so don't need these.

Create a program called Business Plan.py, and type in the following code (you'll need to change the folder path given):

import pandas as pd

import numpy as np

# read excel into Pandas data frame

temp_df = pd.read_excel('C:\wiseowl\Python\purchases.xlsx')

# convert a data frame to a Numpy 2D array

purchases = np.asarray(temp_df)

This should import the data from the Excel workbook, and convert it (via a Pandas dataframe) to a NumPy array. Print the array to check that this has worked:

Print out the dtype property of the array also to show that the presence of the first column is forcing Python to store the data as type object.

Use slicing to set the value of a new variable called volumes equal to the array above, but minus its first column, then run the following command to convert this array to data type integer:

new_volumes = volumes.astype('I')

Print out the dtype property of this latest array to check that the data is indeed now being held as integers.

Create another array called prices to hold the prices you pay in pounds:

Product	Price you pay
Butter	2
Flour	1
Milk	1.5
Eggs	1.5

Show the shape of each of your two arrays:

This should tell you which order they should go in when you mutliply them together.

Use the dot method to multiply your prices array by your new_volumes array to show your total spending per day, then use the sum method to show your total overall spending:

Your spending is peaking on Friday.

Save your program and close it down (if it's anywhere near lunchtime, maybe it's time to reward yourself with a pancake?).

You can unzip this file to see the answers to this exercise, although please remember this is for your personal use only.

You can find other training resources for the subject of this exercise here:

This page has 0 threads

Add a new post

EXERCISE TOPIC

PYTHON EXERCISES

PYTHON EXERCISES

Use NumPy array functions to work out how much your pancake stall is spending on ingredients

Head office

London

Manchester