Programming代做、代写Python程序设计、IDE留学生代做、代写Python语言

日期：2019-11-22 10:24

Task 1: Basic Python Programming

Background

We are going to use ‘PyCharm’, an integrated development environment (IDE) for

Python. If you want to have it on your own devices, please follow the instructions on

the link: https://www.guru99.com/how-to-install-python.html

Install libraries

We need to install 3 Python data analysis libraries: pandas, matplotlib, plotnine, which

helped us on data analysis and visualization. Please click: File-> Settings -> Project:

data_lab -> Project interpreter, then click ‘+’ and type in the library you want to install.

Even the first library is still being installed, you can type in the second and the third

libraries to install several packages in parallel.

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In the status bar, it shows ‘3 processes running’. You can click and see the installing

process, which may take a few minutes.

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Task 1.1: A number guess game

Now, we will use Python’s most common data types: integer, string, Boolean (True,

False), list and dictionary; the most common logic structures: if-else and while; and

the most common operators: =, >, <, ==, to get familiar with the Python basics and

create an interesting guess game.

https://www.dropbox.com/s/eh9puev65i5fk71/guess_num.py?dl=0

a. Copy the codes, run and play.

b. We need to introduce an access control mechanism to the game, as we only want

the right person to play the game.

We can add a simple user name & password check by the data type dictionary:

passwordDictionary= {"geb":"2503", "ray":" ray110", "cuhksz":"666"}

Please check the code and play with the new feature.

https://www.dropbox.com/s/2zqwoytcfyb5kkh/guess_num_access_control.py?dl=0

Can you give a suggestion that how we can give the VIP pass “cuhksz” some

favor to make it easier for this account?

c. We need to introduce a play-limit mechanism, as someone just got addicted to the

game. For example, the game should terminate if you played the game for more than

3 times. Please screenshot your code implementation.

d. Check with Google, explain what does the structure “try-except” do? Why we

need two? Do we really need two?

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Task 2: Analyze Big Data

Task 2.1: Load the data

We are studying the species, hinder foot length and weight of animals captured by

sensors. The data sets are stored in ‘surveys.csv’. Please download it and save it in the

folder of ‘data_lab’.

https://www.dropbox.com/s/u9oi69xk6mmwe0f/surveys.csv?dl=0

We will use the ‘read_csv’ function in the pandas library to load the file ‘surveys.csv’

into a variable, then we can start to deal with the data stored in the variable. Download

‘py_demo_part1.py’ and save it in the folder of ‘data_lab’.

https://www.dropbox.com/s/6mphlaqde441lrc/py_demo_part1.py?dl=0

a. Run the code, print (surveys_df)’ will print the variable that holds all data of

the ‘surveys.csv’ file. The result excerpts the first and the last few lines of the file.

b. Now we comment out ‘print (surveys_df)’, uncomment line 5 & 6, and run

the code.

‘print (surveys_df.dtypes)’ gets the type of each column:

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‘print (type(surveys_df))’ gets the output:

dtype: object

<class 'pandas.core.frame.DataFrame'>

It means the variable ‘surveys_df’ is an object of DataFrame of pandas. By

checking the pandas documentation (https://pandas.pydata.org/pandasdocs/stable/reference/frame.html?highlight=dataframe),

it says DataFrame is a “Twodimensional

size-mutable, potentially heterogeneous tabular data structure”, which

means DataFrame is similar to a spreadsheet in Microsoft Excel.

Note, you may face lots of attributes and functions on using a library (e.g.,

pandas). If we compare a library to a person, attributes, are like this person’s

characteristics; while functions are like this person’s capability. Although

programmers try their best to give attributes and functions nice names to let users

guess their functionalities at the first glance, the best way to find out what they

exactly mean or do is to check with Google or the documentation of that library (e.g.,

the above link is the DataFrame page of the pandas documentation). It shows all the

attributes and functions of DataFrame. For example, it includes the explanation of

‘dtypes’, ‘head()’, ‘tail()’, and other functions in ‘py_demo_part1.py’. Please

uncomment and run the lines of functions you are interested in, and check with the

documentation if you have any doubt.

c. Find a proper indexing function in the documentation page to return the value

of the 3rd row, and the 8th column, which is 37.0. Note, the indexing of Python starts

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from 0. Please write the command down.

d. What if I want to have the values of the first 3 rows, but only the columns from

2nd to 4th, namely, the first 3 rows’ values of month, day and year. Please write the

command down.

e. What if I want to have all the values of the 6th column, namely, the species id.

Please write the command down.

f. What if I want to have all the values of the 6th column, but with the duplicates

removed. Please write the command down.

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Task 3: Visualize Big Data

Download ‘py_demo_part2.py’ and save it in the folder of ‘data_lab’.

https://www.dropbox.com/s/32ozhbhaq7n11rg/py_demo_part2.py?dl=0

a. Run the code, and use the documentation page to explore the plotnine

functions:

https://plotnine.readthedocs.io/en/stable/

b. Please use geom.point() to plot species_id vs hindfoot_length using sex as

the color parameter. In addition, please explain a bit what you observe from the

plot.

c. Please use geom.bar() to plot species_id vs weight using sex as the color

parameter. In addition, please explain a bit what you observe from the plot.

d. Please use geom.point() to plot species_id vs hindfoot_length using sex as

the color parameter, but we want only years of 1979, 1993, 1999, 1977. In

addition, please explain a bit what you observe from the plot.

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END of Tutorial / lab-3