Reverse order of a list - list

I am trying to write a python code to switch the order of the list (from A to Z:input, the output should print from Z to A). My code is not giving me the right output. I need help please
winners = ['Alice Munro', 'Alvin E. Roth', 'Kazuo Ishiguro', 'Malala Yousafzai', 'Rainer ``Weiss', 'Youyou Tu']
z_winners=sorted(winners, key=lambda x: x.split(" ")[-1])
my output is :
['Kazuo Ishiguro', 'Alice Munro', 'Alvin E. Roth', 'Youyou Tu', 'Rainer Weiss', 'Malala Yousafzai']
Instead of :
['Youyou Tu', 'Rainer Weiss', 'Malala Yousafzai', 'Kazuo Ishiguro', 'Alvin E. Roth', 'Alice Munro']

Try this
winners = ['Alice Munro', 'Alvin E. Roth', 'Kazuo Ishiguro', 'Malala Yousafzai', 'Rainer Weiss', 'Youyou Tu']
z_winners=sorted(winners, reverse=True)
print(z_winners)
By the way, you have extra '`' in your list of strings.

Write code to switch the order of the winners list so that it is now Z to A. Then assign this list to the variable z_winners.
winners = ['Alice Munro', 'Alvin E. Roth', 'Kazuo Ishiguro', 'Malala Yousafzai', 'Rainer Weiss', 'Youyou Tu']
winners.sort(reverse=True)
z_winners = winners

Related

How to display "name" and "score" who have highest score?

Here my problem is I have a list of tuples and I need to find out who have the highest score,and corresponding name of the player.
Sample Input:
l=[
('ram' ,16),
('sara' ,13),
('akhil',24),
('vinay',24)
]
Sample Output:
akhil 24
Explanation:
First I sorted the data based on second element in list of tuple.
Among the all players "akhil" and "vinay" has same scores so among the two
people player "akhil" starts first in dictionary or lexicographical order so I printed "akhil" .
Thanks.
Try this.
from collections import OrderedDict
l=[('ram',16),('sara',13),('akhil',24),('vinay',24)]
a = {}
for i in l:
a[i[0]]=i[1]
a = OrderedDict(sorted(a.items(), key=lambda t: t[0]))
print max(a.iterkeys(), key=lambda k: a[k]),a[max(a.iterkeys(), key=lambda k: a[k])]
l=[('ram' ,16),('sara' ,13),('akhil',24),('vinay',24)]
l1=[]
l.sort(key=lambda x:x[1])
print(l)
for i in range(1,len(l)):
if(l[i-1][1]==l[i][1]):
l1.append(l[i][0])
l1.append(l[i-1][0])
z=l[i-1][1]
l1.sort()
print(l1[0],z)

Take first N keys by max value from dict {key:list}

is there have easy way to take first N keys which have max value from they list in dict {key:list}
is there have easy way to take first N keys which have max value from they list in dict {key:list}
def main():
for x in range(len(sale10k)):
timelist.append(sale10k[x][3])
pricesList.append(sale10k[x][4])
if sale10k[x][0] in salesByCategory.keys():
salesByCategory[sale10k[x][0]].append(float(sale10k[x][4]))
else:
salesByCategory[sale10k[x][0]]=[]
salesByCategory[sale10k[x][0]].append(float(sale10k[x][4]))
salesByCategory1={}
for key,value in salesByCategory.items():
salesByCategory1[key]=sum(salesByCategory.get(key))
#fiveLarges=heapq.nlargest(5,salesByCategory1,key=salesByCategory1.get)
salesBycatalog={}
for y in range(len(catalog)):
salesBycatalog[catalog[y][0]]=catalog[y][5]
totalByGroup={}
for key, value in salesBycatalog.items():
if value in totalByGroup.keys():
totalByGroup[value].append(salesByCategory1.get(key))
else:
totalByGroup[value]=[]
totalByGroup[value].append(salesByCategory1.get(key))
print(totalByGroup)
if __name__ == "__main__":
main()
i have 2 files excel.cvs
my output from now is this :
{'POLO SHIRTS': [2609.76, 13339.109999999991, 15622.410000000007], 'APPAREL ACCESSORIES': [22596.24999999999, 20901.099999999995, 31007.8], 'PANTS': [8031.729999999998, 11179.949999999999, 5405.839999999997, 9023.949999999999, 21523.819999999996, 26030.800000000017], 'FOOTWEAR ACCESSORIES': [8686.369999999999], 'GLIDING SP.EQUIPMENT': [22136.399999999987, 27678.920000000006, 14222.21999999999, 30013.37000000001], 'SHOES': [1903.66, 25443.21999999999, 22152.530000000006, 11585.410000000002, 38504.679999999986, 7787.670000000004, 10256.860000000002, 1377.1199999999997, 15459.799999999992, 20919.56000000001, 6299.769999999996, 1555.4499999999998, 17470.460000000006, 29361.220000000034, 4070.9000000000033, 27045.450000000004, 20721.829999999994, 780.55, 24671.590000000015, 13189.570000000002, 6442.700000000001, 6105.390000000005, 12701.659999999998, 29418.89000000001, 7295.620000000001, 26344.420000000002, 3262.12, 11710.460000000006, 3272.2999999999993, 17055.989999999994, 9019.77, 12722.570000000003, 20020.150000000005, 30164.860000000026, 17513.14, 3168.6200000000003, 27008.24, 14585.679999999988, 15273.48, 24172.329999999998, 33968.96000000003, 35480.790000000015, 25150.459999999992, 24207.679999999997, 26909.090000000007, 17692.079999999998, 27844.97999999999, 33847.389999999985, 13266.239999999994, 11757.349999999997, 24469.410000000018, 8214.879999999997, 3966.6899999999964, 5336.910000000003, 27766.659999999978, 24636.97000000002, 21330.829999999994, 10331.680000000004, 19769.529999999995, 20764.439999999984, 2873.509999999999, 23263.23, 15127.240000000003, 13282.320000000003, 32917.03000000001, 17657.12, 9959.55, 21052.779999999995, 16015.79, 2667.2699999999995, 16041.830000000004, 2309.9000000000005, 8095.450000000001, 23628.889999999985, 3846.259999999999, 6795.61, 14608.109999999995, 6422.360000000001, 3241.279999999999, 19220.27999999999, 20836.899999999994, 28446.07000000001, 13984.979999999992, 10006.460000000003, 14417.309999999998, 9069.470000000001, 8081.38, 1766.8899999999999, 19041.750000000004, 3310.279999999999, 3649.49, 11089.069999999994, 10946.420000000002, 16297.91, 3788.1000000000004, 27356.640000000007, 14024.480000000001, 29409.03], 'SUITS': [28587.990000000016, 14337.800000000001], 'BALLS': [25855.07, 15207.729999999992, 25567.809999999987, 8428.509999999998, 15119.609999999995, 26069.969999999983, 29843.490000000023], 'TOPS': [1673.2000000000005, 8673.400000000001, 23610.79999999999, 2090.380000000001], 'HEADWEAR': [2075.3000000000015, 18891.799999999996, 39717.93, 33657.65, 9965.720000000005, 12030.020000000006, 670.9999999999999, 12694.720000000007, 24846.22000000001, 1606.1799999999994, 9993.330000000002, 10154.900000000005], 'HARDWARE ACCESSORIES': [14619.109999999997], 'OTHER SHIRTS': [18013.450000000004], 'PROTECTION GEAR': [26454.929999999997], 'JERSEYS': [23741.06, 38425.269999999975], 'SANDALS/SLIPPERS': [9103.83, 21025.040000000005, 12702.349999999999, 26766.439999999984, 29818.339999999993], 'SHORTS': [14817.77, 29540.92999999998, 9415.059999999996, 14582.480000000001], 'JACKETS': [30096.11000000001, 13372.469999999998, 31145.73000000001, 6011.17, 12225.300000000003, 23485.399999999998, 13889.96], 'SWIMWEAR': [14035.140000000001, 20232.629999999997, 5142.340000000001, 2945.349999999998, 23495.320000000003, 8207.920000000004, 11972.729999999994], 'T-SHIRTS': [11130.700000000004, 8315.83, 8346.719999999998, 27847.550000000007, 22704.759999999995, 7828.200000000002, 17823.379999999997, 2248.46, 9012.14, 7774.72, 12030.049999999996, 4207.649999999999, 21293.16, 3159.4700000000007, 13385.12, 30507.87], 'UNDERWEAR': [10419.31, 31017.909999999993, 2794.590000000002, 18625.990000000005, 21829.879999999994], 'SWEATSHIRTS': [4317.6799999999985, 23453.049999999985, 28176.49000000001], 'TIGHTS': [23823.43999999999, 11180.129999999996], 'BAGS': [13980.240000000007, 18509.50999999999, 20064.309999999998, 22317.360000000004, 17641.04]}
i need this :
SHOES: 1519077.15 €
T-SHIRTS: 207615.78 €
HEADWEAR: 176304.77 €
BALLS: 146092.19 €
JACKETS: 130226.14 €
I have data stored in dict orderBygroup {key-list(of float values)} and need to take first 5 keys with max value.
My second question is - dict salesByCategory1 is make with loping to salesByCategory and sum of all values to receive the total for article number.
Can i get that totals with some smartes way ?
is there have easy way to make that output ?
totalByGroup1={}
for key,value in totalByGroup.items():
totalByGroup1[key]=sum(totalByGroup.get(key))
Create a new dictionary with summed elements. More resources.
sorted5=sorted(totalByGroup1, key=totalByGroup1.get, reverse=True)[:5]
print(sorted5)
sorting and taking the first 5 elements
output is : ['SHOES', 'T-SHIRTS', 'HEADWEAR', 'BALLS', 'JACKETS']
more time, more resurses
for key in sorted5:
print(key,': ','{0:.2f}'.format(totalByGroup1.get(key)))
and now result :
SHOES : 1519077.15
T-SHIRTS : 207615.78
HEADWEAR : 176304.77
BALLS : 146092.19
JACKETS : 130226.14
now lets ask again if we have 4 record in dict wit that data:
a:[1,2,3],b:[6,7,8],c:[4,5,6],d:[9,10,11]
how to get first 2 key,value sorted by max value -->>
d:30,b:21
if we have 1000 record in dict - ?? how to get first N key sorted by max value of list
example go:1563,do:1560,bo:1490,ro:1480 .. etc

how to convert all the values in a list into keys of a Dictionary in Py2.7

I've below lists,
lists=[ ['arya','egg','milk','butter','bread'],
['Jon','butter','pastrie','yogurt','beer'],
['bran','beer','milk','banana','apples'],]
Each list has values in which the first value is the name of a person and rest of all are some food items. I've a task where I've to create a dictionary with these food items as keys and the person as a value as shown below
dict = { 'egg' : set(['arya']),
'milk': set(['arya','bran']),
'butter' : set(['arya','jon']),
'bread' : set(['arya']),
'pastrie' : set(['jon']),
'milk' : set(['bran'])
} # few keys omitted
This is what I did and stopped, dont know how to proceed further,
food,person = [],[]
for i in lists:
food.append(i[1:])
person.append(i[0])
I was able to seperate the first value of each list and append it to a list
and same with food.
Dont know how to proceed further.
started learning python, Any input is highly helpful. kindly share one or two lines of explanation to enlighten this newbie !
Thank you so much.
Using dictionary method setdefault is helpful here.
You of course don't nee to set the slices to a variable, but it makes it easier to read.
d = {}
for l in lists:
name = l[0]
items = l[1:]
for item in items:
d.setdefault(item, set()).add(name)
Use a collections.defaultdict:
lists = [['arya', 'egg', 'milk', 'butter', 'bread'],
['Jon', 'butter', 'pastrie', 'yogurt', 'beer'],
['bran', 'beer', 'milk', 'banana', 'apples']]
from collections import defaultdict
d = defaultdict(set)
for sub in lists:
for v in sub[1:]:
d[v].add(sub[0])
print(d)
Output:
defaultdict(<class 'set'>,
{'bread': {'arya'}, 'yogurt': {'Jon'}, 'beer': {'Jon', 'bran'},
'banana': {'bran'}, 'butter': {'Jon', 'arya'}, 'milk': {'arya',
'bran'}, 'pastrie': {'Jon'}, 'egg': {'arya'}, 'apples': {'bran'}})
For python3 the syntax is a little nicer:
from collections import defaultdict
d = defaultdict(set)
for name, *rest in lists:
for v in rest:
d[v].add(name)

Deleting duplicate x values and their corresponding y values

I am working with a list of points in python 2.7 and running some interpolations on the data. My list has over 5000 points and I have some repeating "x" values within my list. These repeating "x" values have different corresponding "y" values. I want to get rid of these repeating points so that my interpolation function will work, because if there are repeating "x" values with different "y" values it runs an error because it does not satisfy the criteria of a function. Here is a simple example of what I am trying to do:
Input:
x = [1,1,3,4,5]
y = [10,20,30,40,50]
Output:
xy = [(1,10),(3,30),(4,40),(5,50)]
The interpolation function I am using is InterpolatedUnivariateSpline(x, y)
have a variable where you store the previous X value, if it is the same as the current value then skip the current value.
For example (pseudo code, you do the python),
int previousX = -1
foreach X
{
if(x == previousX)
{/*skip*/}
else
{
InterpolatedUnivariateSpline(x, y)
previousX = x /*store the x value that will be "previous" in next iteration
}
}
i am assuming you are already iterating so you dont need the actualy python code.
A bit late but if anyone is interested, here's a solution with numpy and pandas:
import pandas as pd
import numpy as np
x = [1,1,3,4,5]
y = [10,20,30,40,50]
#convert list into numpy arrays:
array_x, array_y = np.array(x), np.array(y)
# sort x and y by x value
order = np.argsort(array_x)
xsort, ysort = array_x[order], array_y[order]
#create a dataframe and add 2 columns for your x and y data:
df = pd.DataFrame()
df['xsort'] = xsort
df['ysort'] = ysort
#create new dataframe (mean) with no duplicate x values and corresponding mean values in all other cols:
mean = df.groupby('xsort').mean()
df_x = mean.index
df_y = mean['ysort']
# poly1d to create a polynomial line from coefficient inputs:
trend = np.polyfit(df_x, df_y, 14)
trendpoly = np.poly1d(trend)
# plot polyfit line:
plt.plot(df_x, trendpoly(df_x), linestyle=':', dashes=(6, 5), linewidth='0.8',
color=colour, zorder=9, figure=[name of figure])
Also, if you just use argsort() on the values in order of x, the interpolation should work even without the having to delete the duplicate x values. Trying on my own dataset:
polyfit on its own
sorting data in order of x first, then polyfit
sorting data, delete duplicates, then polyfit
... I get the same result twice

Python: Summing up a float

If I have a list of strings stored in a variable called b_split[1]. Basically the 1st position in b_split contains these latitude values as a string.
['10.2']
['10.4']
['10.5']
I want to be able to sum them up..
for i in text_file:
latitude = float(b_split[1])
print sum(latitude)
It gives me an error that the 'float' object is not iterable
latitude should be a list
and it should be
latitude.append(float(b_split[1]))
and finally
print sum(latitude)
If you don't need the resulting list and simply want to sum the items, you could try passing the items you care about directly to the sum function:
In [1]: my_list = ['10.2', '10.4', '10.5']
In [2]: sum(float(item) for item in my_list)
Out[2]: 31.1
This creates a generator of the float of each item in your list, and sums each item. As alluded to by #avasal, the reason you are getting your error is because you are actually reassigning latitude on each iteration, and your final result is a float (and not a list/iterable):
In [3]: for item in my_list:
...: my_var = float(item)
...:
In [4]: print my_var
10.5
Therefore when you try to sum it, you get the error you see above because sum sums the elements of an iterable. Since you can't iterate over a float, you get the not iterable error.