Description
A GUI for plotting PV data
1 Introduction
In assignment 1 you wrote a simple tool for getting data from PV arrays.
For this assignment you will write a GUI for plotting this data. A user of
your program will be able to choose a date, which PV array to look at and
what data is to be plotted.
2 Assignment Tasks
For each class and method that you write you need to provide a suitable
comment giving a description and where necessary the type and any preconditions. You should use the triple-quote commenting style.
2.1 Download file
The file assign2.py is for your assignment. Add your name and student
number in the space provided. When you have completed your assignment
you will submit the file assign2.py containing your solution to the assignment.
The file already contains some code (in two parts). Do not modify any of this
code! The first part should be left at the beginning of the file and consists of
some import statements and support code. The second part should appear
at the end of your code. NOTE: You will loose marks if you don’t follow
these instructions.
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2.2 Write the code
Finally, write your solution to the assignment making sure you have included suitable comments. Your solution should include at least the following
classes.
2.2.1 PVData Class
This class is used to hold the PV data for a given date. This class must
define at least the following methods. You are required to use a dictionary
to store the array power data. You should also use separate lists to store the
temperature and sunlight data.
• __init__(self) that initializes the PV data to use yesterday’s data.
• change_date(self, date) changes the data to be for the given date
(making this date the ‘current date’). If the same date is used (i.e. no
change) then it must not extract the same data from the server again.
• get_date(self) that returns the date for the stored data.
• get_time(self, time_index) that returns the time for the given index of the time data.
• get_temperature(self) that returns the list of temperature values
for the current date.
• get_sunlight(self) that returns the list of sunlight values for the
current date.
• get_power(self, array) that returns the list of power output for the
current date and the the given array (the array name).
• get_cumulative_energy(self, array) (for CSSE7030 students
only) computes and returns the list of cumulative power values for the
current date and the the given array (the array name).
Example (given the length of data, we have used slicing below to extract a
small sublist, also only the error messages are displayed – not the traceback)
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>>> pvd = PVData()
>>> pvd.change_date(’13-09-2014’)
>>> pvd.get_date()
’13-09-2014’
>>> pvd.get_time(300)
’10:00’
>>> pvd.get_temperature()[300:304]
[22.0, 22.0, 21.5, 21.5]
>>> pvd.get_sunlight()[300:304]
[252.7, 252.7, 216.3, 216.3]
>>> pvd.get_power(’UQ Centre, St Lucia’)[300:304]
[80495, 74765, 68285, 65250]
>>> pvd.get_power(’All Arrays Combined’)[300:304]
[288155, 270165, 248465, 239472]
>>> pvd.get_cumulative_energy(’All Arrays Combined’)[300:304]
[99963090, 100233255, 100481720, 100721192]
>>> get_data_for_date(’’)
ValueError: No date given.
>>> get_data_for_date(’20-10-2050’)
ValueError: Date must be before today.
>>> get_data_for_date(’20_10_2014’)
ValueError: Invalid date: ’20_10_2014’
>>>
2.2.2 Plotter Class
This class is responsible for doing the plotting and should inherit from
Canvas.
2.2.3 OptionsFrame Class
This class is the ’widget’ used for choosing options and should inherit from
Frame. It consists of the following:
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For CSSE1001 students
• A row of three Checkbutton’s so the user can choose what data is to
be displayed (Power, Temperature and Sunlight ).
• An Entry box where the user can enter a date.
• A Button to apply the choice of date.
• An OptionMenu allowing the user to choose which array to display data
for. (The default choice is All Arrays Combined.)
For CSSE7030 students
• A row of three Radiobutton’s to choose between No Power, Instantaneous Power and Cumulative Power.
• A row of two Checkbutton’s so the user can choose what data (other
than power) is to be displayed (Temperature and Sunlight).
• An Entry box where the user can enter a date.
• A Button to apply the choice of date and array choice.
• An OptionMenu allowing the user to choose which array to display data
for. (The default choice is All Arrays Combined.)
2.2.4 PVPlotApp Class
This is the top-level class for the GUI. It is responsible for creating and
managing instances of the above classes.
At the top of the application the current date is displayed and if the left
mouse button is clicked (and held down) a vertical line is drawn on the
canvas and the data at that time, along with the time, is displayed next to
the date. Dragging will shift the line and change the data displayed. The
displayed data values should correspond to the values which are visible in the
plot (e.g. only show the temperature at the top if the temperature checkbox
is selected).
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Note that, if the user enters an invalid date string, or if the date is valid
but out of range (e.g. in the future) then the support file code will raise an
exception. You need to catch such exceptions and display them in a po-up
tkMessageBox window.
Details of the required GUI layout is shown in the examples listed below.
CSSE1001 and CSSE7030 students must adhere to the CSSE1001 layout
and CSSE7030 layout respectively.
NOTE: You must use pack (rather than grid) to do your GUI
layout.
2.3 Examples
The course web page contains the following examples.
• Screenshots showing the GUI in use (CSSE1001 layout)
• Screenshots showing the GUI in use (CSSE7030 layout)
• Screencast showing the application in action.
2.4 Hints
For OptionsFrame, when the user changes the date or the PV array the
system needs to possibly fetch new data and to then display the required
data. In order to do this you need to call a method of PVPlotApp. This can
be achieved in one of two ways – make the PVPlotApp object or the required
method an argument to the OptionsFrame constructor.
For Plotter you will need to access the plot data. Probably the simplest
approach is to make the PVData object an argument to the Plotter constructor. You might also find it useful to access the OptionsFrame object and a
method to change what is displayed at the top of the application window.
For redrawing, either because the window has been resized or because the
data to be displayed has changed, it’s easiest to delete everything on the
canvas (delete(ALL)) and draw all the required lines and polygons again.
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3 Assessment and Marking Criteria
In addition to providing a working solution to the assignment problem, the
assessment will involve discussing your code submission with a tutor. This
discussion will take place in the practical session you have signed up to in
week 12. You must attend that session in order to obtain marks for the
assignment.
In preparation for your discussion with a tutor you may wish to consider:
• any parts of the assignment that you found particularly difficult, and
how you overcame them to arrive at a solution;
• whether you considered any alternative ways of implementing a given
function;
• where you have known errors in your code, their cause and possible
solutions (if known).
It is also important that you can explain to the tutor how each of the functions
that you have written operates (for example, if you have used a for loop or
a while loop in a function, why this was the right choice).
Marks will be awarded based on a combination of the correctness of your code
and on your understanding of the code that you have written. A technically
correct solution will not elicit a pass mark unless you can demonstrate that
you understand its operation.
We will mark your assignment according to the following criteria.
Criteria Mark
Your code is mostly complete, correct, clear, succinct and well
commented. You are able to explain your code.
8 – 10
Your code has some problems OR you have some problems
explaining your code.
4 – 7
Your code is clearly incomplete, incorrect, too complex or
hard to understand OR you have major problems explaining
your code.
1 – 3
Your work has little or no academic merit. 0
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A partial solution will be marked. If your partial solution causes problems
in the Python interpreter please comment out that code and we will mark
that.
Please read the section in the course profile about plagiarism.
4 Assignment Submission
You must submit your completed assignment electronically through Blackboard.
Please read
http://www.library.uq.edu.au/ask-it/blackboard-assessment
for information on submitting through Blackboard.
You should electronically submit your copy of the file assign2.py (use this
name – all lower case).
You may submit your assignment multiple times before the deadline – only the
last submission will be marked. After each submission please use Blackboard
to check that the file you submitted was the one you intended to submit.
Make sure the file is called assign2.py and not, for example, assign2.py.py
Late submission of the assignment will not be accepted. In the event of
exceptional personal or medical circumstances that prevent you from handing
in the assignment on-time, you should contact the lecturer in charge and
be prepared to supply appropriate documentary evidence. You should be
prepared to submit whatever work you have completed at the deadline, if
required. Requests for extensions should be made as soon as possible, and
preferably before the assignment due date.
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