NUMPY: AVERAGE OF ROWS

Question

'''
In a matrix, or 2-d array X, the averages (or means) of the elements of rows is called row means.

Task
Given a 2D array, return the rowmeans.

Input Format
First line: two integers separated by spaces, the first indicates the rows of matrix X (n) and the second indicates the columns of X (p)
Next n lines: values of the row in X

Output Format
An numpy 1d array of values rounded to the second decimal.

2 2
1.5 1
2 2.9

Sample Output
[1.25 2.45]

'''

n, p = [int(x) for x in input().split()]

list = []

new_list = []

for i in range (n):
list.append(input().split())

import numpy as np

arr = np.array(list)

mean = arr.mean(axis = 1)
print (mean)

#This code generates error as input data is a string. Explain ways to convert all strings into int/float before appending it to list or to change the data type of all the items in an array.

Answer 1

n, p = [int(x) for x in input().split()]
list = []
for i in range(n):
list.append([float(j) for j in input().split()])
import numpy as np
arr = np.array(list, dtype='f')
mean = arr.mean(axis=1)
print(mean.round(2))

Answer 2

noteve Your solution is wonderful. ☺️ However, you just need to add the round method to the 'mean' variable assignment or to the print line to pass the spec criteria. Eg:

mean = arr.mean(axis=1).round(2)

Answer 3

# Try this:

n, p = [int(x) for x in input().split()]

list = []

for i in range (n):
list.append([float(j) for j in input().split()])

import numpy as np

arr = np.array(list)

mean = arr.mean(axis = 1)
print (mean)

# Update me if it still not solved. Thanks!!

Answer 4

Working 5/5:

n, p = [int(x) for x in input().split()]
l=list()

for i in range(n):
l.append([float(j) for j in input().split()])

import numpy as np

arr=np.array(l)
arrz=arr.reshape(n,p)
mn=np.mean(arrz,axis=1)
print(np.round(mn,decimals=2))

Any queries feel free to dm

Answer 5

#Solution -
import numpy as np
rows, columns = [int(x) for x in input().split()]
matrix = []
for row in range(rows):
matrix.append(input().split())
matrix = list(np.float_(matrix))
#print(matrix)
average = np.average(matrix, axis=1)
print(average.round(2))

Answer 6

@AJ
I tried all solutions in sololearn and it always fails me in testcases any help would be appreciated

Answer 7

The major challenge here is to understand what you are doing, and this test makes this terrible. So, my suggestion is to solve this by the following approach:

1. Make the code understandable by a human (test it in your playground), so you can understand how the tricky input works, but the human messages in the input() calls will break when you copy the code to the test;
2. With your code running ok, go to the test, remove the human messages, and submit the code.

FIRST PART - Make the code understandable by a human (test it in your playground):
# This code will work in your playground but will break in the test.
import numpy as np
rows, columns = [int(x) for x in input('Enter 2 int dimensions n and p (separated by spaces): ').split()]
matrix = []
for row in range(rows):
matrix.append(input(f'Enter {columns} values for {row+1} (separated by spaces): ').split())
matrix = list(np.float_(matrix))
average = np.average(matrix, axis=1)
print(average.round(2))

SECOND PART - With your code running ok, go to the test, remove the human messages, and submit the code.
# This code will work in will NOT break in the test.
import numpy as np
rows, columns = [int(x) for x in input().split()]
matrix = []
for row in range(rows):
matrix.append(input().split())
matrix = list(np.float_(matrix))
average = np.average(matrix, axis=1)
print(average.round(2))

Submit and celebrate.

Answer 8

Here goes the path for the solution in a manner that will help you understand it step-by-step.

Errata: in my last answer here, when I mentioned "the playground", I wanted to say "your PC".

So here we go...

The major challenge in this test is to first understand what you are doing by running the code in your PC/notebook, because the neither the test interface nor the Playground interface will help with it. So, my suggestion is to solve this by the following approach:

1. Make the code understandable by a human (test it in YOUR PC OR NOTEBOOK), so you can understand how the tricky input works, but the human messages in the input() calls will break when you copy the code to the test or will not be understandable in the playground;
2. With your code running ok IN YOUR COMPUTER, go to the test, remove the human messages, and submit the code.

FIRST PART - Make the code understandable by a human (test it in YOUR COMPUTER):
# This code will work in YOUR COMPUTER but will break in the test.
import numpy as np
rows, columns = [int(x) for x in input('Enter 2 int dimensions n and p (separated by spaces): ').split()]
matrix = []
for row in range(rows):
matrix.append(input(f'Enter {columns} values for {row+1} (separated by spaces): ').split())
matrix = list(np.float_(matrix))
average = np.average(matrix, axis=1)
print(average.round(2))

SECOND PART - With your code running ok, go to the test, remove the human messages, and submit the code.
# This code will work in will NOT break in the test.
import numpy as np
rows, columns = [int(x) for x in input().split()]
matrix = []
for row in range(rows):
matrix.append(input().split())
matrix = list(np.float_(matrix))
average = np.average(matrix, axis=1)
print(average.round(2))

Submit and celebrate.

Answer 9

CHANDAN ROY

Sent solution in DM.

Answer 10

Task
Given a 2D array feature matrix X and a vector y, return the coefficient vector; see the formula.

First line: two integers separated by spaces, the first indicates the rows of the feature matrix X (n) and the second indicates the columns of X (p)
Next n lines: values of the row in the feature matrix
Last line: p values of target y

MY CODE
import numpy as np
rows, columns = [int(x) for x in input().split()]
matrix = []
for row in range(rows):
matrix.append(input().split())
matrix = list(np.float_(matrix))
#print(matrix)
average = np.average(matrix, axis=1)
print(average.round(2))

Error: Not satisfied any Test case

Answer 11

import numpy as np

arr = np.array([input().split() for x in range(n)]).astype(float)
mean = arr.mean(axis=1).round(2)
print(mean)

Answer 12

import numpy as np
arr=np.array([[1.5,1],[2,2.9]])
print(arr.mean(axis=1))

Answer 13

import numpy as np
import re
n, p = [int(x) for x in input().split()]
lista = []
for i in range(n):
lista.append(input().split())
sol = str(np.array(lista).astype(np.float16).mean(axis=1).round(2))
removeSpaces = re.sub("\s\s+", ' ', sol)
print(removeSpaces)

Answer 14

Rajesh Das unfortunately your solution failed test case 3&4

Answer 15

I Am AJ ! Rafique Sir, help!!