# Python NumPy: Array Object Exercises, Practice, Solution

## Python NumPy Array Object [100 exercises with solution]

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1. Write a Python program to print the NumPy version in your system. Go to the editor
Click me to see the sample solution

2. Write a Python program to count the number of characters (character frequency) in a string. Go to the editor
Expected Output:
Original List: [12.23, 13.32, 100, 36.32]
One-dimensional numpy array: [ 12.23 13.32 100. 36.32]
Click me to see the sample solution

3. Create a 3x3 matrix with values ranging from 2 to 10. Go to the editor
Expected Output:
[[ 2 3 4]
[ 5 6 7]
[ 8 9 10]]
Click me to see the sample solution

4. Write a Python program to get a string from a given string where all occurrences of its first char have been changed to '\$', except the first char itself. Go to the editor
[ 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
Update sixth value to 11
[ 0. 0. 0. 0. 0. 0. 11. 0. 0. 0.]

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5. Write a Python program to get a single string from two given strings, separated by a space and swap the first two characters of each string. Go to the editor
Expected Output:
[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]
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6. Write a Python program to reverse an array (first element becomes last). Go to the editor
Original array:
[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]
Reverse array:
[37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12]
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7. Write a Python program to an array converted to a float type. Go to the editor
Sample output:
Original array
[1, 2, 3, 4]
Array converted to a float type:
[ 1. 2. 3. 4.]
Click me to see the sample solution

8. Write a Python program to create a 2d array with 1 on the border and 0 inside. Go to the editor
Expected Output:
Original array:
[[ 1. 1. 1. 1. 1.]
[ 1. 1. 1. 1. 1.]
[ 1. 1. 1. 1. 1.]
[ 1. 1. 1. 1. 1.]
[ 1. 1. 1. 1. 1.]]
1 on the border and 0 inside in the array
[[ 1. 1. 1. 1. 1.]
[ 1. 0. 0. 0. 1.]
[ 1. 0. 0. 0. 1.]
[ 1. 0. 0. 0. 1.]
[ 1. 1. 1. 1. 1.]]
Click me to see the sample solution

9. Write a Python program to remove the nth index character from a nonempty string. Go to the editor
Expected Output:
Original array:
[[ 1. 1. 1.]
[ 1. 1. 1.]
[ 1. 1. 1.]]
1 on the border and 0 inside in the array
[[ 0. 0. 0. 0. 0.]
[ 0. 1. 1. 1. 0.]
[ 0. 1. 1. 1. 0.]
[ 0. 1. 1. 1. 0.]
[ 0. 0. 0. 0. 0.]]
Click me to see the sample solution

10. Write a Python program to change a given string to a new string where the first and last chars have been exchanged. Go to the editor
Checkerboard pattern:
[[0 1 0 1 0 1 0 1]
[1 0 1 0 1 0 1 0]
[0 1 0 1 0 1 0 1]
[1 0 1 0 1 0 1 0]
[0 1 0 1 0 1 0 1]
[1 0 1 0 1 0 1 0]
[0 1 0 1 0 1 0 1]
[1 0 1 0 1 0 1 0]]
Click me to see the sample solution

11. Write a Python program to convert a list and tuple into arrays. Go to the editor
List to array:
[1 2 3 4 5 6 7 8]
Tuple to array:
[[8 4 6]
[1 2 3]]
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12. Write a Python program to append values to the end of an array. Go to the editor
Expected Output:
Original array:
[10, 20, 30]
After append values to the end of the array:
[10 20 30 40 50 60 70 80 90]
Click me to see the sample solution

13. Write a Python program to create an empty and a full array. Go to the editor
Expected Output:
[ 6.93270651e-310 1.59262180e-316 6.93270559e-310 6.93270665e-310]
[ 6.93270667e-310 6.93270671e-310 6.93270668e-310 6.93270483e-310]
[ 6.93270668e-310 6.93270671e-310 6.93270370e-310 6.93270488e-310]]
[[6 6 6]
[6 6 6]
[6 6 6]]
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14. Write a Python program to convert the values of Centigrade degrees into Fahrenheit degrees. Centigrade values are stored into a NumPy array. Go to the editor
Sample Array [0, 12, 45.21 ,34, 99.91]
Expected Output:
Values in Fahrenheit degrees:
[ 0. 12. 45.21 34. 99.91]
Values in Centigrade degrees:
[-17.77777778 -11.11111111 7.33888889 1.11111111 37.72777778]
Click me to see the sample solution

15. Write a Python program to find the real and imaginary parts of an array of complex numbers. Go to the editor
Expected Output:
Original array [ 1.00000000+0.j 0.70710678+0.70710678j]
Real part of the array:
[ 1. 0.70710678]
Imaginary part of the array:
[ 0. 0.70710678]
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16. Write a Python program to find the number of elements of an array, length of one array element in bytes and total bytes consumed by the elements. Go to the editor
Expected Output:
Size of the array: 3
Length of one array element in bytes: 8
Total bytes consumed by the elements of the array: 24
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17. Write a Python program to test whether each element of a 1-D array is also present in a second array. Go to the editor
Expected Output:
Array1: [ 0 10 20 40 60]
Array2: [0, 40]
Compare each element of array1 and array2
[ True False False True False]
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18. Write a Python program to find common values between two arrays. Go to the editor
Expected Output:
Array1: [ 0 10 20 40 60]
Array2: [10, 30, 40]
Common values between two arrays:
[10 40]
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19. Write a Python program to get the unique elements of an array. Go to the editor
Expected Output:
Original array:
[10 10 20 20 30 30]
Unique elements of the above array:
[10 20 30]
Original array:
[[1 1]
[2 3]]
Unique elements of the above array:
[1 2 3]
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20. Write a Python program to find the set difference of two arrays. The set difference will return the sorted, unique values in array1 that are not in array2. Go to the editor
Expected Output:
Array1: [ 0 10 20 40 60 80]
Array2: [10, 30, 40, 50, 70, 90]
Set difference between two arrays:
[ 0 20 60 80]
Click me to see the sample solution

21. Write a Python program to find the set exclusive-or of two arrays. Set exclusive-or will return the sorted, unique values that are in only one (not both) of the input arrays. Go to the editor
Array1: [ 0 10 20 40 60 80]
Array2: [10, 30, 40, 50, 70]
Unique values that are in only one (not both) of the input arrays:
[ 0 20 30 50 60 70 80]
Click me to see the sample solution

22. Write a Python program to find the union of two arrays. Union will return the unique, sorted array of values that are in either of the two input arrays. Go to the editor
Array1: [ 0 10 20 40 60 80]
Array2: [10, 30, 40, 50, 70]
Unique sorted array of values that are in either of the two input arrays:
[ 0 10 20 30 40 50 60 70 80]
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23. Write a Python program to test if all elements in an array evaluate to True. Go to the editor
Note: 0 evaluates to False in python.
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24. Write a Python program to test whether any array element along a given axis evaluates to True. Go to the editor
Note: 0 evaluates to False in python.
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25. Write a Python program to construct an array by repeating. Go to the editor

Sample array: [1, 2, 3, 4]
Expected Output:
Original array
[1, 2, 3, 4]
Repeating 2 times
[1 2 3 4 1 2 3 4]
Repeating 3 times
[1 2 3 4 1 2 3 4 1 2 3 4]

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26. Write a Python program to repeat elements of an array. Go to the editor
Expected Output:
[3 3 3 3]
[1 1 2 2 3 3 4 4]
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27. Write a Python program to find the indices of the maximum and minimum values along the given axis of an array. Go to the editor
Original array: [1 2 3 4 5 6]
Maximum Values: 5
Minimum Values: 0
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28. Write a Python program compare two arrays using numpy. Go to the editor
Array a: [1 2]
Array b: [4 5]
a > b
[False False]
a >= b
[False False]
a < b
[ True True]
a <= b
[ True True]
Click me to see the sample solution

29. Write a Python program to sort an along the first, last axis of an array. Go to the editor
Sample array: [[2,5],[4,4]]
Expected Output:
Original array:
[[4 6]
[2 1]]
Sort along the first axis:
[[2 1]
[4 6]]
Sort along the last axis:
[[1 2]
[4 6]]
Click me to see the sample solution

30. Write a Python program to sort pairs of first name and last name return their indices. (first by last name, then by first name). Go to the editor
first_names = (Betsey, Shelley, Lanell, Genesis, Margery)
last_names = (Battle, Brien, Plotner, Stahl, Woolum)
Expected Output:
[1 3 2 4 0]
Click me to see the sample solution

31. Write a Python program to get the values and indices of the elements that are bigger than 10 in a given array. Go to the editor
Original array:
[[ 0 10 20]
[20 30 40]]
Values bigger than 10 = [20 20 30 40]
Their indices are (array([0, 1, 1, 1]), array([2, 0, 1, 2]))
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32. Write a Python program to save a NumPy array to a text file. Go to the editor
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33. Write a Python program to find the memory size of a NumPy array. Go to the editor
Expected Output:
128 bytes
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34. Write a Python program to create an array of ones and an array of zeros. Go to the editor
Expected Output:
Create an array of zeros
Default type is float
[[ 0. 0.]]
Type changes to int
[[0 0]]
Create an array of ones
Default type is float
[[ 1. 1.]]
Type changes to int
[[1 1]]
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35. Write a Python program to change the dimension of an array. Go to the editor
Expected Output:
6 rows and 0 columns
(6,)
(3, 3) -> 3 rows and 3 columns
[[1 2 3]
[4 5 6]
[7 8 9]]
Change array shape to (3, 3) -> 3 rows and 3 columns
[[1 2 3]
[4 5 6]
[7 8 9]]
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36. Write a Python program to create a contiguous flattened array. Go to the editor
Original array:
[[10 20 30]
[20 40 50]]
New flattened array:
[10 20 30 20 40 50]
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37. Write a Python program to create a 2-dimensional array of size 2 x 3 (composed of 4-byte integer elements), also print the shape, type and data type of the array. Go to the editor
Expected Output:

(2, 3)
int32
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38. Write a Python program to count occurrences of a substring in a string. Go to the editor
Reshape 3x2:
[[1 2]
[3 4]
[5 6]]
Reshape 2x3:
[[1 2 3]
[4 5 6]]
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39. Write a Python program to change the data type of an array. Go to the editor
Expected Output:
[[ 2 4 6]
[ 6 8 10]]
Data type of the array x is: int32
New Type: float64
[[ 2. 4. 6.]
[ 6. 8. 10.]]
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40. Write a Python program to reverse words in a string. Go to the editor
Expected Output:
[[2 2 2 2 2]
[2 2 2 2 2]
[2 2 2 2 2]]
[[2 2 2 2 2]
[2 2 2 2 2]
[2 2 2 2 2]]
Click me to see the sample solution

41. Write a Python program to create an array of 10's with the same shape and type of an given array. Go to the editor
Sample array: x = np.arange(4, dtype=np.int64)
Expected Output:
[10 10 10 10]
Click me to see the sample solution

42. Write a Python program to create a 3-D array with ones on the diagonal and zeros elsewhere. Go to the editor
Expected Output:
[[ 1. 0. 0.]
[ 0. 1. 0.]
[ 0. 0. 1.]]
Click me to see the sample solution

43. Write a Python program to create a 2-D array whose diagonal equals [4, 5, 6, 8] and 0's elsewhere. Go to the editor
Expected Output:
[[4 0 0 0]
[0 5 0 0]
[0 0 6 0]
[0 0 0 8]]
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44. Write a Python program to create a 1-D array going from 0 to 50 and an array from 10 to 50. Go to the editor
Expected Output:
Array from 0 to 50:
[ 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]
Array from 10 to 50:
[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]
Click me to see the sample solution

45. Write a Python program to Create a 1-D array of 30 evenly spaced elements between 2.5. and 6.5, inclusive. Go to the editor
Expected Output:
[ 2.5 2.63793103 2.77586207 2.9137931 3.05172414 3.18965517
3.32758621 3.46551724 3.60344828 3.74137931 3.87931034 4.01724138
4.15517241 4.29310345 4.43103448 4.56896552 4.70689655 4.84482759
4.98275862 5.12068966 5.25862069 5.39655172 5.53448276 5.67241379
5.81034483 5.94827586 6.0862069 6.22413793 6.36206897 6.5 ]
Click me to see the sample solution

46. Write a Python program to to create a 1-D array of 20 element spaced evenly on a log scale between 2. and 5., exclusive. Go to the editor
Expected Output:
[ 100. 141.25375446 199.5262315 281.83829313
398.10717055 562.34132519 794.32823472 1122.0184543
1584.89319246 2238.72113857 3162.27766017 4466.83592151
6309.5734448 8912.50938134 12589.25411794 17782.79410039
25118.8643151 35481.33892336 50118.72336273 70794.57843841]
Click me to see the sample solution

47. Write a Python program to create an array which looks like below array. Go to the editor
Expected Output:
[[ 0. 0. 0.]
[ 1. 0. 0.]
[ 1. 1. 0.]
[ 1. 1. 1.]]
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48. Write a Python program to create an array which looks like below array. Go to the editor
Expected Output:
[[ 2 3 4]
[ 5 6 7]
[ 0 9 10]
[ 0 0 13]]
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49. Write a Python program to collapse a 3-D array into one dimension array. Go to the editor
Expected Output:
3-D array:
[[ 1. 0. 0.]
[ 0. 1. 0.]
[ 0. 0. 1.]]
One dimension array:
[ 1. 0. 0. 0. 1. 0. 0. 0. 1.]
Click me to see the sample solution

50. Write a Python program to find the 4th element of a specified array. Go to the editor
Expected Output:
[[ 2 4 6]
[ 6 8 10]]
Forth e1ement of the array:
6
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51. Write a Python program to interchange two axes of an array. Go to the editor
Sample array: [[1 2 3]]
Expected Output:
[[1]
[2]
[3]]
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52. Write a Python program to create an array of 10's with the same shape and type of an given array. Go to the editor
Expected Output:
(3, 4, 2)
(4, 2, 3)
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53. Write a Python program to create an array of 10's with the same shape and type of an given array. Go to the editor
Move the following 3rd array axes to first position.
(2,3,4,5)
Sample Expected Output:
(2, 5, 3, 4)
Click me to see the sample solution

54. Write a Python program to convert specified inputs to arrays with at least one dimension. Go to the editor
Expected Output:
[ 12.]
[[ 0. 1. 2.]
[ 3. 4. 5.]]
[array([1]), array([3, 4])]
Click me to see the sample solution

55. Write a Python program to view inputs as arrays with at least two dimensions, three dimensions. Go to the editor
Expected Output:
View inputs as arrays with at least two dimensions:
[10]
[[ 0. 1.]
[ 2. 3.]]
View inputs as arrays with at least three dimensions:
[[[15]]]
[[[ 0.]
[ 1.]
[ 2.]]]
Click me to see the sample solution

56. Write a Python program to insert a new axis within a 2-D array. Go to the editor
2-D array of shape (3, 4).
Expected Output:
New shape will be will be (3, 1, 4).
Click me to see the sample solution

57. Write a Python program to remove single-dimensional entries from a specified shape. Go to the editor
Specified shape: (3, 1, 4)
Expected Output: (3, 4)
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58. Write a Python program to concatenate two 2-dimensional arrays. Go to the editor
Expected Output:
Sample arrays: ([[0, 1, 3], [5, 7, 9]], [[0, 2, 4], [6, 8, 10]]
Expected Output:
[[ 0 1 3 0 2 4]
[ 5 7 9 6 8 10]]
Click me to see the sample solution

59. Write a Python program to convert 1-D arrays as columns into a 2-D array. Go to the editor
Sample array: (10,20,30), (40,50,60)
Expected Output:
[[10 40]
[20 50]
[30 60]]
Click me to see the sample solution

60. Write a Python program to convert (in sequence depth wise (along third axis)) two 1-D arrays into a 2-D array. Go to the editor
Sample array: (10,20,30), (40,50,60)
Expected Output:
[[[10 40]]
[[20 50]]
[[30 60]]]
Click me to see the sample solution

61. Write a Python program to split an array of 14 elements into 3 arrays, each of which has 2, 4, and 8 elements in the original order. Go to the editor
Expected Output:
Original array: [ 1 2 3 4 5 6 7 8 9 10 11 12 13 14]
After splitting:
[array([1, 2]), array([3, 4, 5, 6]), array([ 7, 8, 9, 10, 11, 12, 13, 14])]
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62. Write a Python program to split an of array of shape 4x4 it into two arrays along the second axis. Go to the editor
Sample array :
[[ 0 1 2 3]
[ 4 5 6 7]
[ 8 9 10 11]
[12 13 14 15]]
Expected Output:
[array([[ 0, 1],
[ 4, 5],
[ 8, 9],
[12, 13]]), array([[ 2, 3],
[ 6, 7],
[10, 11],
[14, 15]]), array([], shape=(4, 0), dtype=int64)]
Click me to see the sample solution

63. Write a Python program to get the number of nonzero elements in an array. Go to the editor
Expected Output:
Original array:
[[ 0 10 20]
[20 30 40]]
Number of non zero elements in the above array:
5
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64. Write a Python program to create a 5x5 matrix with row values ranging from 0 to 4. Go to the editor
Original array:
[[ 0. 0. 0. 0. 0.]
[ 0. 0. 0. 0. 0.]
[ 0. 0. 0. 0. 0.]
[ 0. 0. 0. 0. 0.]
[ 0. 0. 0. 0. 0.]]
Row values ranging from 0 to 4.
[[ 0. 1. 2. 3. 4.]
[ 0. 1. 2. 3. 4.]
[ 0. 1. 2. 3. 4.]
[ 0. 1. 2. 3. 4.]
[ 0. 1. 2. 3. 4.]]
Click me to see the sample solution

65. Write a Python program to test if specified values are present in an array. Go to the editor
Expected Output:
Original array:
[[ 1.12 2. 3.45]
[ 2.33 5.12 6. ]]
True
False
True
False
True

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66. Write a Python program to create a vector of size 10 with values ranging from 0 to 1, both excluded. Go to the editor
Expected Output:
[ 0.09090909 0.18181818 0.27272727 0.36363636 0.45454545 0.54545455
0.63636364 0.72727273 0.81818182 0.90909091]
Click me to see the sample solution

67. Write a Python program to make an array immutable (read-only). Go to the editor
Expected Output:
Test the array is read-only or not:
Try to change the value of the first element:
Traceback (most recent call last):
File "19236bd0-0bd9-11e7-a232-c706d0968eb6.py", line 6, in
x[0] = 1
ValueError: assignment destination is read-only
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68. Write a Python program (using numpy) to sum of all the multiples of 3 or 5 below 100. Go to the editor
Expected Output:
[ 3 5 6 9 10 12 15 18 20 21 24 25 27 30 33 35 36 39 40 42 45 48 50 51 54
55 57 60 63 65 66 69 70 72 75 78 80 81 84 85 87 90 93 95 96 99]
2318
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69. Write a Python program to create an array with 10^3 elements. Go to the editor
Expected Output:
[ 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.
- - - - - - - - - - - - - - - - - - - -
972. 973. 974. 975. 976. 977. 978. 979. 980. 981. 982. 983.
984. 985. 986. 987. 988. 989. 990. 991. 992. 993. 994. 995.
996. 997. 998. 999.]
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70. Write a Python program to create display every element of an numpy array. Go to the editor
Expected Output:
0 1 2 3 4 5 6 7 8 9 10 11
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71. Write a Python program to create and display every element of an numpy array in Fortran order. Go to the editor
Expected Output:
Elements of the array in Fortan array:
0 4 8 1 5 9 2 6 10 3 7 11
Click me to see the sample solution

72. Write a Python program to create a 5x5x5 cube of 1's. Go to the editor
Expected Output:
[[[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]]

[[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]]

[[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]]

[[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]]

[[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]]]
Click me to see the sample solution

73. Write a Python program to create an array of (3, 4) shape, multiply every element value by 3 and display the new array. Go to the editor
Expected Output:
Original array elements:
[[ 0 1 2 3]
[ 4 5 6 7]
[ 8 9 10 11]]
New array elements:
[[ 0 3 6 9]
[12 15 18 21]
[24 27 30 33]]
Click me to see the sample solution

74. Write a Python program to combine a one and a two dimensional array together and display their elements. Go to the editor
Expected Output:
One dimensional array:
[0 1 2 3]
Two dimensional array:
[[0 1 2 3]
[4 5 6 7]]
0:0
1:1
2:2
3:3
0:4
1:5
2:6
3:7
Click me to see the sample solution

75. Write a Python program to create an array of zeros and three column types (integer, float, character). Go to the editor
Expected Output:
[(1, 2., b'Albert Einstein') (2, 2., b'Edmond Halley')
(3, 3., b'Gertrude B. Elion')]
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76. Write a Python program to create a function cube which cubes all the elements of an array. Go to the editor
Expected Output:
[ 1 8 27]
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77. Write a Python program to create an array of (3, 4) shape and convert the array elements in smaller chunks. Go to the editor
Expected Output:
Original array elements:
[[ 0 1 2 3]
[ 4 5 6 7]
[ 8 9 10 11]]
[0 4 8]
[1 5 9]
[ 2 6 10]
[ 3 7 11]
Click me to see the sample solution

78. Write a Python program to create a record array from a (flat) list of arrays. Go to the editor
Sample arrays: [1,2,3,4], ['Red', 'Green', 'White', 'Orange'], [12.20,15,20,40]
Expected Output:
(1, 'Red', 12.2)
(2, 'Green', 15.0)
(3, 'White', 20.0)
Click me to see the sample solution

79. Write a Python program to generate a generic 2D Gaussian-like array. Go to the editor
Expected Output:
2D Gaussian-like array:
[[ 0.36787944 0.44822088 0.51979489 0.57375342 0.60279818 0.60279818
0.57375342 0.51979489 0.44822088 0.36787944]
[ 0.44822088 0.54610814 0.63331324 0.69905581 0.73444367 0.73444367
0.69905581 0.63331324 0.54610814 0.44822088]
.......... [ 0.44822088 0.54610814 0.63331324 0.69905581 0.73444367 0.73444367
0.69905581 0.63331324 0.54610814 0.44822088]
[ 0.36787944 0.44822088 0.51979489 0.57375342 0.60279818 0.60279818
0.57375342 0.51979489 0.44822088 0.36787944]]
Click me to see the sample solution

80. Write a Python program to convert a NumPy array into Python list structure. Go to the editor
Expected Output:
Original array elements:
[[0 1]
[2 3]
[4 5]]
Array to list:
[[0, 1], [2, 3], [4, 5]]
Click me to see the sample solution

81. Write a Python program to access an array by column. Go to the editor
Expected Output:
Original array elements:
[[0 1]
[2 3]
[4 5]]
Access an array by column:
First column:
[0 1]
Second column:
[2 3]
Third column:
[4 5]
Click me to see the sample solution

82. Write a Python program to convert a numpy array of float values to a numpy array of integer values. Go to the editor
Expected Output:
Original array elements:
[[ 12. 12.51]
[ 2.34 7.98]
[ 25.23 36.5 ]]
Conver float values to intger values:
[[12 12]
[ 2 7]
[25 36]]
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83. Write a Python program to convert a NumPy array into Python list structure. Go to the editor
Expected Output:
Original array elements:
[ 0.26153123 0.52760141 0.5718299 0.5927067 0.7831874 0.69746349
0.35399976 0.99469633 0.0694458 0.54711478]
Print array values with precision 3:
[ 0.262 0.528 0.572 0.593 0.783 0.697 0.354 0.995 0.069 0.547]
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84. Write a Python program to suppresses the use of scientific notation for small numbers in numpy array. Go to the editor
Expected Output:
Original array elements:
[ 1.60000000e-10 1.60000000e+00 1.20000000e+03 2.35000000e-01]
Print array values with precision 3:
[ 0. 1.6 1200. 0.235]
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85. Write a Python program to create a numpy array of 10 integers from a generator. Go to the editor

Expected Output:
[0 1 2 3 4 5 6 7 8 9]
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86. Write a Python program to how to add an extra column to an numpy array. Go to the editor

Expected Output:
[[ 10 20 30 100]
[ 40 50 60 200]]
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87. Write a Python program to find unique rows in a numpy array. Go to the editor

Expected Output:
Original array:
[[20 20 20 0]
[ 0 20 20 20]
[ 0 20 20 20]
[20 20 20 0]
[10 20 20 20]]
Unique rows of the above array:
[[ 0 20 20 20]
[10 20 20 20]
[20 20 20 0]]
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88. Write a Python program to replace all elements of numpy array that are greater than specified array. Go to the editor

Expected Output:
Original array:
[[ 0.42436315 0.48558583 0.32924763]
[ 0.7439979 0.58220701 0.38213418]
[ 0.5097581 0.34528799 0.1563123 ]]
Replace all elements of the said array with .5 which are greater than. 5
[[ 0.42436315 0.48558583 0.32924763]
[ 0.5 0.5 0.38213418]
[ 0.5 0.34528799 0.1563123 ]]
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89. Write a Python program to remove specific elements in a numpy array. Go to the editor

Expected Output:
Original array:
[ 10 20 30 40 50 60 70 80 90 100]
Delete first, fourth and fifth elements:
[ 20 30 60 70 80 90 100]
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90. Write a Python program to remove the negative values in a numpy array with 0. Go to the editor

Expected Output:
Original array:
[-1 -4 0 2 3 4 5 -6]
Replace the negative values of the said array with 0:
[0 0 0 2 3 4 5 0]
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91. Write a Python program to remove all rows in a numpy array that contain non-numeric values. Go to the editor
Expected Output:
Original array:
[[ 1. 2. 3.]
[ 4. 5. nan]
[ 7. 8. 9.]
[ 1. 0. 1.]]
Remove all non-numeric elements of the said array
[[ 1. 2. 3.]
[ 7. 8. 9.]
[ 1. 0. 1.]]
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92. Write a Python program to remove all rows in a numpy array that contain non-numeric values. Go to the editor
Sample array :
a = np.array([97, 101, 105, 111, 117])
b = np.array(['a','e','i','o','u'])
Note: Select the elements from the second array corresponding to elements in the first array that are greater than 100 and less than 110
Expected Output:
Original arrays
[ 97 101 105 111 117]
['a' 'e' 'i' 'o' 'u']
Elements from the second array corresponding to elements in the first
array that are greater than 100 and less than 110:
['e' 'i']
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93. Write a Python program to get the magnitude of a vector in numpy. Go to the editor
Expected Output:
Original array:
[1 2 3 4 5]
Magnitude of the vector:
7.4161984871
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94. Write a Python program to count the frequency of unique values in numpy array. Go to the editor
Expected Output:
Original array:
[10 10 20 10 20 20 20 30 30 50 40 40]
Frequency of unique values of the said array:
[[10 20 30 40 50]
[ 3 4 2 2 1]]
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95. Write a Python program to check whether the numpy array is empty or not. Go to the editor
Expected Output:
2
0
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96. Write a Python program to divide each row by a vector element. Go to the editor
Expected Output:
Original array:
[[20 20 20]
[30 30 30]
[40 40 40]]
Vector:
[20 30 40]
[[ 1. 1. 1.]
[ 1. 1. 1.]
[ 1. 1. 1.]]
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97. Write a Python program to print all the values of an array. Go to the editor
Expected Output:
[[ 0. 0. 0. 0.]
[ 0. 0. 0. 0.]
[ 0. 0. 0. 0.]
[ 0. 0. 0. 0.]]
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98. Write a Python program to convert the raw data in an array to a binary string and then create an array from this data. Go to the editor
Expected Output:
Original array:
[ 10. 20. 30.]
Binary string array:
b'\x00\x00\x00\x00\x00\x00\$@\x00\x00\x00\x00\x00\x004@\x00\x00\x00\x00\x00\x00>@'
Array using fromstring():
[ 10. 20. 30.]
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99. Write a Python program to sum and compute the product of a numpy array elements. Go to the editor
Expected Output:
Original array:
[ 10. 20. 30.]
Sum of the array elements:
60.0
Product of the array elements:
6000.0
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100. Write a Python program to take values from a source array and put them at specified indices of another array. Go to the editor
Expected Output:
[ 10. 10. 20. 30. 30.]
Put 0 and 40 in first and fifth position of the above array
Array x after put two values: [ 0. 10. 20. 30. 40.]
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