Coding the Matrix作业Python Lab及提交方法

Coding the Matrix: Linear Algebra through Computer Science Applications 

  这是一门用python实现矩阵运算的课，第一次作业就感觉对python的提高很大，用到了各种数据类型。

  代码如下：

## Task 1
minutes_in_week = 60*24*7

## Task 2
remainder_without_mod = 2304811-2304811//47*47

## Task 3
divisible_by_3 = (673+909)/3==0

## Task 4
x = -9
y = 1/2
statement_val = 2**(y+1/2) if x+10<0 else 2**(y-1/2)

## Task 5
first_five_squares = { x*x for x in {1,2,3,4,5} }

## Task 6
first_five_pows_two = { 2**x for x in {0,1,2,3,4} }

## Task 7: enter in the two new sets
X1 = { 1, 2, 3 }
Y1 = { 4, 11, 17 }

## Task 8: enter in the two new sets
X2 = { 1, 2, 0 }
Y2 = { 4, 8, 16 }

## Task 9
base = 10
digits = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
three_digits_set = { base**2*x+base*y+z for x in digits for y in digits for z in digits }

## Task 10
S = {1, 2, 3, 4}
T = {3, 4, 5, 6}
S_intersect_T = { x for x in S if x in T }

## Task 11
L_average = sum([20, 10, 15, 75])/len([20, 10, 15, 75]) # average of: [20, 10, 15, 75]

## Task 12
LofL = [[.25, .75, .1], [-1, 0], [4, 4, 4, 4]]
LofL_sum = sum({sum(LofL[x]) for x in range(0,len(LofL))}) # use form: sum([sum(...) ... ])

## Task 13
cartesian_product = [[x,y] for x in {'A','B','C'} for y in {1,2,3} ] # use form: [ ... {'A','B','C'} ... {1,2,3} ... ]

## Task 14
S = {-4, -2, 1, 2, 5, 0}
zero_sum_list = [ (x,y,z) for x in S for y in S for z in S if x+y+z==0 ] 

## Task 15
exclude_zero_list = [ (x,y,z) for x in S for y in S for z in S if (x+y+z==0) and (x or y or z) ]

## Task 16
first_of_tuples_list = [ (x,y,z) for x in S for y in S for z in S if (x+y+z==0) and (x or y or z) ][0]

## Task 17
L1 = [1,1,2] # <-- want len(L1) != len(list(set(L1)))
L2 = [2,1,3] # <-- same len(L2) == len(list(set(L2))) but L2 != list(set(L2))

## Task 18
odd_num_list_range = { x for x in range(1,100,2)}

## Task 19
L = ['A','B','C','D','E']
range_and_zip = list(zip(list(range(5)),L))

## Task 20
list_sum_zip = [x+y for (x,y) in zip([10,25,40],[1,15,20])]

## Task 21
dlist = [{'James':'Sean', 'director':'Terence'}, {'James':'Roger', 'director':'Lewis'}, {'James':'Pierce', 'director':'Roger'}]
k = 'James'
value_list = [d[k] for d in dlist]

## Task 22
dlist = [{'Bilbo':'Ian','Frodo':'Elijah'},{'Bilbo':'Martin','Thorin':'Richard'}]
k = 'Bilbo'
value_list_modified_1 = [d[k] if k in d else 'NOT PRESENT' for d in dlist] # <-- Use the same expression here
k = 'Frodo'
value_list_modified_2 = [d[k] if k in d else 'NOT PRESENT' for d in dlist] # <-- as you do here

## Task 23
square_dict = {x:x**2 for x in range(100)}

## Task 24
D = {'red','white','blue'}
identity_dict = {x:x for x in D}

## Task 25
base = 10
digits = set(range(10))
representation_dict = { base**2*x+base*y+z:[x,y,z] for x in digits for y in digits for z in digits}

## Task 26
d = {0:1000.0, 1:1200.50, 2:990}
names = ['Larry', 'Curly', 'Moe']
listdict2dict = { names[x]:y for (x,y) in d.items() }

## Task 27
def nextInts(L): return [ x+1 for x in L ]

## Task 28
def cubes(L): return [ x**3 for x in L ] 

## Task 29
def dict2list(dct, keylist): return [ dct[x] for x in keylist ]

## Task 30 
def list2dict(L, keylist): return { x:y for (x,y) in zip(keylist,L) } 

  评分系统有一些bug，如task2不能用括号等，如果出错可以比对一下。

  提交方法：

  在linux下提交按照说明即可，但在windows下面，就要费好大一番功夫了。

  由于submit_python_lab.py里面默认待提交的py文件在当前目录下，必须把py文件和submit_python_lab.py文件拷贝到python3的安装文件夹下面。我用的是python3.3，因此要拷贝到的目录为：C:\Python33。论坛说双击submit_python_lab.py输入账号密码即可，为了方便我使用bat脚本文件运行：

C:\Python33\python C:\Python33\submit_python_lab.py