w3resource

NumPy: Random Exercises, Practice, Solution

NumPy Random [17 exercises with solution]

[An editor is available at the bottom of the page to write and execute the scripts.]

1. Write a NumPy program to generate five random numbers from the normal distribution. Go to the editor
Expected Output:
[-0.43262625 -1.10836787 1.80791413 0.69287463 -0.53742101]
Click me to see the sample solution

2. Write a NumPy program to generate six random integers between 10 and 30. Go to the editor
Expected Output:
[20 28 27 17 28 29]
Click me to see the sample solution

3. Write a NumPy program to create a 3x3x3 array with random values. Go to the editor
Expected Output:
[[[ 0.48941799 0.58722213 0.43453926]
[ 0.94497547 0.81081709 0.1510409 ]
[ 0.66657127 0.29494755 0.48047144]]
[[ 0.02287253 0.95232614 0.32264936]
[ 0.67009741 0.25458304 0.16290913]
[ 0.15520198 0.86826529 0.9679322 ]]
[[ 0.13503103 0.02042211 0.24683897]
[ 0.97852158 0.22374748 0.10798856]
[ 0.62032646 0.5893892 0.16958144]]]
Click me to see the sample solution

4. Write a NumPy program to create a 5x5 array with random values and find the minimum and maximum values. Go to the editor
Expected Output:
Original Array:
[[ 0.96336355 0.12339131 0.20295196 0.37243578 0.88105252]
[ 0.93228246 0.67470158 0.38103235 0.32242645 0.40610231]
[ 0.3113495 0.31688 0.79189089 0.08676434 0.60829874]
[ 0.30360149 0.94316317 0.98142491 0.77222542 0.51532195]
[ 0.97392305 0.16669609 0.81377917 0.2165645 0.00121611]]
Minimum and Maximum Values:
0.00121610921757 0.981424910368
Click me to see the sample solution

5. Write a NumPy program to create a random 10x4 array and extract the first five rows of the array and store them into a variable. Go to the editor
Sample Output:
Original array:
[[ 0.38593391 0.52823544 0.8994567 0.22097238]
[ 0.16639229 0.74964167 0.58102198 0.2811601 ]
[ 0.56447627 0.42575759 0.71297527 0.91099347]
[ 0.00261548 0.0064798 0.66096109 0.54514293]
[ 0.7216008 0.95815426 0.53370551 0.28116107]
[ 0.16252081 0.26191659 0.40883164 0.60653848]
[ 0.55934457 0.37814126 0.63287808 0.01856616]
[ 0.03788236 0.22705078 0.82024426 0.83019741]
[ 0.31140166 0.43926341 0.38685152 0.92402934]
[ 0.00581032 0.83925377 0.95246879 0.28570894]]
First 5 rows of the above array:
[[ 0.38593391 0.52823544 0.8994567 0.22097238]
[ 0.16639229 0.74964167 0.58102198 0.2811601 ]
[ 0.56447627 0.42575759 0.71297527 0.91099347]
[ 0.00261548 0.0064798 0.66096109 0.54514293]
[ 0.7216008 0.95815426 0.53370551 0.28116107]]

Click me to see the sample solution

6. Write a NumPy program to shuffle numbers between 0 and 10 (inclusive). Go to the editor
Sample Output:
[5 7 9 0 2 3 1 6 8 4]
Same result using permutation():
[6 7 4 5 8 2 3 9 0 1]
Click me to see the sample solution

7. Write a NumPy program to normalize a 3x3 random matrix. Go to the editor
Sample output:
Original Array:
[[ 0.87311805 0.96651849 0.98078621]
[ 0.26407141 0.46784012 0.69947627]
[ 0.20013296 0.75510414 0.26290783]]
After normalization:
[[ 0.86207941 0.98172337 1. ]
[ 0.08190378 0.34292711 0.63964803]
[ 0. 0.71090613 0.08041325]]
Click me to see the sample solution

8. Write a NumPy program to create a random vector of size 10 and sort it. Go to the editor
Expected Output:
Original array:
[ 0.73123073 0.67714015 0.95615347 0.4759837 0.88789818 0.6910404 2
0.59996415 0.26144489 0.51618644 0.89943882]
Sorted array:
[ 0.26144489 0.4759837 0.51618644 0.59996415 0.67714015 0.6910404 2
0.73123073 0.88789818 0.89943882 0.95615347]
Click me to see the sample solution

9. Write a NumPy program to find the nearest value from a given value in an array. Go to the editor
Expected Output:
4.96138509939
Click me to see the sample solution

10. Write a NumPy program to check two random arrays are equal or not. Go to the editor
Sample Output:
First array:
[1 0 1 0 1 1]
Second array:
[0 0 1 1 1 0]
Test above two arrays are equal or not!
False
Click me to see the sample solution

11. Write a NumPy program to create random vector of size 15 and replace the maximum value by -1. Go to the editor
Sample output:
Original array:
[ 0.34807512 0.76714463 0.40242311 0.5634299 0.84972926 0.92247789
0.93791571 0.5127047 0.50796265 0.50074454 0.26067194 0.07207825
0.04927934 0.95309433 0.14043974]
Maximum value replaced by -1:
[ 0.34807512 0.76714463 0.40242311 0.5634299 0.84972926 0.92247789
0.93791571 0.5127047 0.50796265 0.50074454 0.26067194 0.07207825
0.04927934 -1. 0.14043974]
Click me to see the sample solution

12. Write a NumPy program to find point by point distances of a random vector with shape (10,2) representing coordinates. Go to the editor
Sample output:
[[ 0. 0.09871078 0.42100075 0.75597269 0.52281832 0.13721998
0.1761711 0.28689498 0.42061575 0.61315509]
[ 0.09871078 0. 0.43978557 0.71086596 0.59696144 0.14701023
0.26602812 0.19254215 0.36762701 0.68776127]
.....
[ 0.42061575 0.36762701 0.30691429 0.34395028 0.63326713 0.29974614
0.47787697 0.39922329 0. 0.70954707]
[ 0.61315509 0.68776127 0.4097455 0.85714768 0.09080178 0.55976699
Click me to see the sample solution

13. Write a NumPy program to find the most frequent value in an array. Go to the editor
Sample Output:
Original array:
[6 9 5 1 7 5 1 0 1 5 5 0 8 9 0 7 0 7 6 5 1 1 9 5 3 8 7 9 6 3 4 5 9 7 2 7 0
2 2 6]
Most frequent value in the above array:
5
Click me to see the sample solution

14. Write a NumPy program to convert cartesian coordinates to polar coordinates of a random 10x2 matrix representing cartesian coordinates. Go to the editor
Expected Output:
[ 0.89225122 0.68774813 0.20392039 1.22093243 1.24435921 1.00358852
0.37378547 0.8534585 0.31999648 0.567451 ]
[ 1.02751197 1.26964967 0.02567519 0.85386412 0.73152767 0.45822494
1.50634505 1.47389983 0.80818521 0.33001182]
Click me to see the sample solution

15. Write a NumPy program to find the closest value (to a given scalar) in an array. Go to the editor
Original array:
[ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74
75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99]
Value to compare:
34.99062268928913
35
Click me to see the sample solution

16. Write a NumPy program to get the n largest values of an array. Go to the editor
Sample output:
Original array:
[0 1 2 3 4 5 6 7 8 9]
[9]
Click me to see the sample solution

17. Write a NumPy program to create a three-dimension array with shape (300,400,5) and set to a variable. Fill the array elements with values using unsigned integer (0 to 255). Go to the editor
Sample output:
[[[215 42 224 219 43]
[166 69 15 133 255]
[105 95 54 37 201]
...
[240 22 66 232 132]
[ 13 85 53 220 170]
[249 62 221 146 69]]
[[ 73 79 148 132 164]
[ 3 93 98 138 200]
[174 34 31 208 130]
...
[143 20 219 154 85]
[219 190 170 227 246]
[ 39 14 127 230 158]]]
Click me to see the sample solution

Python-Numpy Code Editor:

More to Come !

Do not submit any solution of the above exercises at here, if you want to contribute go to the appropriate exercise page.

Test your Python skills with w3resource's quiz



Share this Tutorial / Exercise on : Facebook and Twitter

Python: Tips of the Day

Getting rid of unwanted characters:

You can get rid of whitespaces or any specific character using strip methods in Python. You can use either plain strip for both sides, lstrip for the left side and rstrip for the right side only.

str="+++Welcome python+++"
str.strip()

print(str)

Output:

+++Welcome python+++