Week 1
這周我們 ed 系統(tǒng)上有一個 Quiz 和四個 Challenges。
[TOC]
Quiz 1
這個 Quiz 寫好了輸入輸出的代碼，讓你補充其中對于其 mapping 相關一些操作的運算和判斷過程。
題目要求
See pdf and stub.
0.5 mark for print statement
0.5 mark for list of integers that are not keys of the mapping
0.5 mark for mapping as a list
1 mark for one-to-one part of the mapping
然后 pdf 文檔中給出了 test cases 和希望的輸出結果。限于篇幅，這里我只放其中一個。詳情請見 Quiz 1 要求 -- OneDrive 分享 。
在 shell 中輸入：
（根據(jù)個人習慣，shell 可以為 terminal、iterm、powershell等。在 unix (MacOS included) 和 linux 下，個人推薦直接用 terminal（終端）就很好了）
$ python3 quiz_1.py
Enter two integers: 0 8
期望得到的輸出：
The generated mapping is:
{2: 4, 3: 8, 4: 7, 5: 7}
The mappings's so-called "keys" make up a set whose number of elements is 4.
The list of integers between 1 and 8 that are not keys of the mapping is:
[1, 6, 7, 8]
Represented as a list, the mapping is:
[None, None, 4, 8, 7, 7, None, None, None]
The one-to-one part of the mapping is:
{2: 4, 3: 8}
你需要做
- 數(shù)一下 keys of mapping 有幾個。
- 列出非 keys of mapping 的數(shù)。
- 將 mapping 列表輸出，其中沒有 mapping 的用
None填充。 - 尋找唯一的 mapping 并輸出。
代碼實現(xiàn)
(by Harriet and Eric Martin, All Right Reserved)
Anyone who is plagiarisming, which include copying, Inappropriate paraphrasing, Collusion, Inappropriate citation, Self-plagiarism will undermine academic integrity and is not tolerated at UNSW.
# Written by Harriet and Eric Martin for COMP9021
import sys
from random import seed, randrange
try:
arg_for_seed, upper_bound = (abs(int(x)) + 1 for x in input('Enter two integers: ').split())
except ValueError:
print('Incorrect input, giving up.')
sys.exit()
seed(arg_for_seed)
mapping = {}
num_map = 0
# Generate Mapping
for i in range(1, upper_bound):
r = randrange(-upper_bound // 2, upper_bound)
if r > 0:
mapping[i] = r;
num_map += 1;
print('\nThe generated mapping is:')
print(' ', mapping)
mapping_as_a_list = []
one_to_one_part_of_mapping = {}
nonkeys = []
# Calculate the value of keys
for i in range (1, upper_bound):
if i not in mapping.keys():
nonkeys.append (i);
# Generate mapping as a list
for i in range (0, upper_bound):
if i in mapping:
mapping_as_a_list.append(mapping[i]);
else:
mapping_as_a_list.append(None);
# Generate one by one mapping
mapping_value = []
for key, value in mapping.items():
mapping_value.append(value);
num_mpvl = 0;
for key_another, value_another in mapping.items():
if value == value_another:
num_mpvl += 1;
# Only output values that its number of mapping values equals to 1
if num_mpvl == 1:
one_to_one_part_of_mapping[key] = value;
# Output
print()
print(f'The mappings\'s so-called "keys" make up a set whose number of elements is {num_map}.');
print('\nThe list of integers between 1 and', upper_bound - 1, 'that are not keys of the mapping is:')
print(' ', nonkeys)
print('\nRepresented as a list, the mapping is:')
print(' ', mapping_as_a_list)
# Recreating the dictionary, inserting keys from smallest to largest,
# to make sure the dictionary is printed out with keys from smallest to largest.
one_to_one_part_of_mapping = {key: one_to_one_part_of_mapping[key]
for key in sorted(one_to_one_part_of_mapping)
}
print('\nThe one-to-one part of the mapping is:')
print(' ', one_to_one_part_of_mapping)
Challenge 1: Temperature conversion tables
題目要求
Study the program fahrenheit_to_celsius.py and run it in the Terminal window, executing "python3 fahrenheit_to_celsius.py". Then complete the program celsius_to_fahrenheit.py that displays a conversion table from Celsius degrees to Fahrenheit degrees, with the former ranging from 0 to 100 in steps of 10; run it and check your solution with the Run and Submit buttons, respectively.
See commands_and_expected_outputs.txt for expected output.
其中提到的兩個文件：
- fahrenheit_to_celsius.py
# Written by Eric Martin for COMP9021
'''
Prints out a conversion table of temperatures from Fahrenheit to Celsius degrees,
with the former ranging from 0 to 300 in steps of 20.
'''
min_temperature = 0
max_temperature = 300
step = 20
# \t: A tab
print('Fahrenheit\tCelsius')
# We let fahrenheit take the values
# - min_temperature
# - min_temperature + step
# - min_temperature + 2 * step
# - min_temperature + 3 * step
# ...
# up to the largest value smaller than max_temperature + step
for fahrenheit in range(min_temperature, max_temperature + step, step):
celsius = 5 * (fahrenheit - 32) / 9
# {:10d} or {:10}: fahrenheit as a decimal number in a field of width 10
# {:7.1f}: celsius as a floating point number in a field of width 7
# with 1 digit after the decimal point
print(f'{celsius:10}\t{fahrenheit:7.1f}')
- commands_and_expected_outputs.txt
TEST 1 BEGIN
$ python3 celsius_to_fahrenheit.py?
Celsius Fahrenheit
0 32
10 50
20 68
30 86
40 104
50 122
60 140
70 158
80 176
90 194
100 212
TEST 1 END
直接在 shell 中運行第一個文件 "fahrenheit_to_celsius.py" 的結果是：
$ python3 fahrenheit_to_celsius.py
Fahrenheit Celsius
0 -17.8
20 -6.7
40 4.4
60 15.6
80 26.7
100 37.8
120 48.9
140 60.0
160 71.1
180 82.2
200 93.3
220 104.4
240 115.6
260 126.7
280 137.8
300 148.9
你需要做
- 研究老師給的 "fahrenheit_to_celsius.py" 如何輸出華氏度到攝氏度的轉換表
- 寫一個 "celsius_to_fahrenheit.py" 逆向輸出攝氏度到華氏度的轉換表
代碼實現(xiàn)
(by Harriet and Eric Martin, All Right Reserved)
Anyone who is plagiarisming, which include copying, Inappropriate paraphrasing, Collusion, Inappropriate citation, Self-plagiarism will undermine academic integrity and is not tolerated at UNSW.
'''
Prints out a conversion table of temperatures from Celsius to Fahrenheit degrees,
the former ranging from 0 to 100 in steps of 10.
'''
# Written by Harriet for COMP9021
min_temperature = 0
max_temperature = 100
step = 10
print('Celsius\tFahrenheit')
for celsius in range(min_temperature, max_temperature + step, step):
fahreheit = 9 * celsius / 5 + 32;
fahreheit = int(fahreheit);
print(f'{celsius:7d}\t{fahreheit:10d}');
Challenge 2: Max element and span in a list
題目要求
Study the program max_in_list.py and run it in the Terminal window, executing "python3 max_in_list.py". Then complete the program span.py that prompts the user for a seed for the random number generator, and for a strictly positive number, nb_of_elements, generates a list of nb_of_elements random integers between 0 and 99, prints out the list, computes the difference between the largest and smallest values in the list without using the builtins min() and max(), prints it out, and check that the result is correct using the builtins; run it and check your solution with the Run and Submit buttons, respectively.
See commands_and_expected_outputs.txt for expected outputs and sample inputs.
你需要做
代碼實現(xiàn)
(by Harriet and Eric Martin, All Right Reserved)
Anyone who is plagiarisming, which include copying, Inappropriate paraphrasing, Collusion, Inappropriate citation, Self-plagiarism will undermine academic integrity and is not tolerated at UNSW.
# Written by Harriet for COMP9021
'''
Prompts the user for a seed for the random number generator,
and for a strictly positive number, nb_of_elements.
Generates a list of nb_of_elements random integers between 0 and 99, prints out the list,
computes the difference between the largest and smallest values in the list without using
the builtins min() and max(), prints it out, and check that the result is correct using
the builtins.
'''
from random import seed, randint
import sys
try:
arg_for_seed = int(input('Input a seed for the random number generator: '))
except ValueError:
print('Input is not an integer, giving up.')
sys.exit()
try:
nb_of_elements = int(input('How many elements do you want to generate? '))
except ValueError:
print('Input is not an integer, giving up.')
sys.exit()
if nb_of_elements <= 0:
print('Input should be strictly positive, giving up.')
sys.exit()
seed(arg_for_seed)
L = [randint(0, 99) for _ in range(nb_of_elements)]
print('\nThe list is:', L)
max_element = 0
min_element = 99
for e in L:
if e > max_element:
max_element = e
if e < min_element:
min_element = e
print('\nThe maximum difference between largest and smallest values in this list is:', max_element-min_element)
print('Confirming with builtin operations:', max(L)-min(L))
Challenge 3: Classifying elements in a list
題目要求
The operators /, // and % are used for floating point division, integer division, and remainder, respectively. Study the program modulo_4.py and run it in the Terminal window, executing "python3 modulo_4.py". Then complete program intervals.py that prompts the user for a strictly positive integer, nb_of_elements, generates a list of nb_of_elements random integers between 0 and 19, prints out the list, computes the number of elements strictly less than 5, 10, 15 and 20, and prints those out; run it and check your solution with the Run and Submit buttons, respectively.
See commands_and_expected_outputs.txt for expected outputs and sample inputs.
你需要做
代碼實現(xiàn)
(by Harriet and Eric Martin, All Right Reserved)
Anyone who is plagiarisming, which include copying, Inappropriate paraphrasing, Collusion, Inappropriate citation, Self-plagiarism will undermine academic integrity and is not tolerated at UNSW.
Challenge 4: Statistics on numbers in a list
題目要求
Complete the program mean_median_standard_deviation.py that prompts the user for a strictly positive integer, nb_of_elements, generates a list of nb_of_elements random integers between - 50 and 50, prints out the list, computes the mean, the median and the standard deviation in two ways, that is, using or not the functions from the statistics module, and prints them out.
To compute the median, the easiest way is to first sort the list with the builtin sort() method.
See commands_and_expected_outputs.txt for expected outputs and sample inputs.
你需要做
代碼實現(xiàn)
(by Harriet and Eric Martin, All Right Reserved)
Anyone who is plagiarisming, which include copying, Inappropriate paraphrasing, Collusion, Inappropriate citation, Self-plagiarism will undermine academic integrity and is not tolerated at UNSW.
