Data Preprocessing with NumPy Flashcards

Author: Ivan Kitov Cards: 132

Our Data Preprocessing with NumPy Flashcards are a specialized guide to mastering data preprocessing techniques with NumPy, a core Python library for numerical computing. The deck is structured to help learners cultivate a deep understanding of NumPy's capabilities, beginning with the basics and progressing to advanced data manipulation. The deck starts by introducing fundamental concepts like Python, package, library, module, and NumPy. It highlights the critical role of NumPy in numerical computing, especially when compared to pandas. It also discusses NumPy arrays (ndarrays)—central to NumPy's operations—and explains their advantages over standard Python lists and operations like concatenation and broadcasting. The detailed cards explain the properties and methods of arrays—for example, dtype for data types, such as np.int32 and np.float16. They also cover attributes like shape and size, and various indexing techniques, such as negative indices and stepwise slicing. The flashcards emphasize practical skills like type casting and assigning values, which are crucial for effective data cleaning and data transformation. The Data Preprocessing with NumPy Flashcards cover data generation and manipulation, including NumPy documentation and functions like np.empty, np.ones, np.zeros, and np.full. They also explore array creation functions such as np.arange and random generators like np.random, np.normal (NumPy norm), and np.choice, which are essential for simulations and stochastic processes. The deck also includes statistical functions like poisson distribution, binomial distribution, logistic distribution, exponential distribution, and geometric distribution, offering users tools for statistical analysis within NumPy. It also covers methods like np.transpose for reshaping data and file operations, such as np.load, np.savetxt, and np.genfromtxt for efficient data handling. Additionally, the flashcards explore statistical analysis using NumPy’s robust functions like np.min, np.max, np.mean, np.median, np.percentile, and np.corrcoef, enabling comprehensive evaluations. The flashcards also explain advanced data manipulation techniques like conditional slicing, np.squeeze, and broadcasting rules for effective complex array operations. The flashcards cover key data preprocessing methods. These include np.isnan for detecting NaN values, np.delete for data removal, and np.argsort for array sorting. They also detail techniques for shuffling data and stacking arrays, which are crucial in data preprocessing for machine learning. This deck is an indispensable tool for anyone wanting to learn how to preprocess data in Python and leverage NumPy for data analysis. It provides an in-depth look at the library’s extensive features and equips users with the skills needed to execute sophisticated data preprocessing tasks. Advance your data preprocessing skills in Python using our Data Preprocessing with NumPy Flashcards today!

Our Data Preprocessing with NumPy Flashcards are a specialized guide to mastering data preprocessing techniques with NumPy, a core Python library for numerical computing. The deck is structured to help learners cultivate a deep understanding of NumPy's capabilities, beginning with the basics and progressing to advanced data manipulation. The deck starts by introducing fundamental concepts like Python, package, library, module, and NumPy. It highlights the critical role of NumPy in numerical computing, especially when compared to pandas. It also discusses NumPy arrays (ndarrays)—central to NumPy's operations—and explains their advantages over standard Python lists and operations like concatenation and broadcasting. The detailed cards explain the properties and methods of arrays—for example, dtype for data types, such as np.int32 and np.float16. They also cover attributes like shape and size, and various indexing techniques, such as negative indices and stepwise slicing. The flashcards emphasize practical skills like type casting and assigning values, which are crucial for effective data cleaning and data transformation. The Data Preprocessing with NumPy Flashcards cover data generation and manipulation, including NumPy documentation and functions like np.empty, np.ones, np.zeros, and np.full. They also explore array creation functions such as np.arange and random generators like np.random, np.normal (NumPy norm), and np.choice, which are essential for simulations and stochastic processes. The deck also includes statistical functions like poisson distribution, binomial distribution, logistic distribution, exponential distribution, and geometric distribution, offering users tools for statistical analysis within NumPy. It also covers methods like np.transpose for reshaping data and file operations, such as np.load, np.savetxt, and np.genfromtxt for efficient data handling. Additionally, the flashcards explore statistical analysis using NumPy’s robust functions like np.min, np.max, np.mean, np.median, np.percentile, and np.corrcoef, enabling comprehensive evaluations. The flashcards also explain advanced data manipulation techniques like conditional slicing, np.squeeze, and broadcasting rules for effective complex array operations. The flashcards cover key data preprocessing methods. These include np.isnan for detecting NaN values, np.delete for data removal, and np.argsort for array sorting. They also detail techniques for shuffling data and stacking arrays, which are crucial in data preprocessing for machine learning. This deck is an indispensable tool for anyone wanting to learn how to preprocess data in Python and leverage NumPy for data analysis. It provides an in-depth look at the library’s extensive features and equips users with the skills needed to execute sophisticated data preprocessing tasks. Advance your data preprocessing skills in Python using our Data Preprocessing with NumPy Flashcards today!

Explore the Flashcards:

1 of 132

Python

A high-level, interpreted programming language known for its clear syntax and readability,

widely used for data analysis, artificial intelligence, scientific computing, and more.

2 of 132

Package

A collection of pre-written functions, classes, and methods which are capable of handling

and manipulating data and calculating results.

3 of 132

Library

A collection of modules or functions that can be included in applications to provide specific functionality or features, reducing the amount of code developers need to write.

4 of 132

Module

A file containing Python definitions and statements. Modules enable logical organization of Python code and facilitate reusable code libraries.

5 of 132

NumPy

A Python library that provides support for multi-dimensional arrays and matrices,

and a collection of mathematical functions to operate on these arrays.

Works in a lower-level language, which means shorter computation times.

6 of 132

Pandas

A Python library that provides data manipulation and analysis tools,

particularly offering data structures and operations for manipulating numerical tables and time series. Stores multiple types of data simultaneously.

7 of 132

Convention

A set of recommended practices or coding styles that programmers agree to follow to ensure consistency and improve readability in their codebase.

8 of 132

Alias

A shorter or alternative name defined for a module or object in Python, used to shorten code or avoid naming conflicts.

9 of 132

Function

A block of organized, reusable code that performs a specific task; functions provide better modularity for applications and a high degree of code reusing.

10 of 132

Universal Functions

Functions in NumPy that operate element-wise on arrays, providing fast and efficient mathematical functionalities across arrays.

11 of 132

Method

A function that is associated with an object or class in object-oriented programming and is called using that object.

12 of 132

Class

In object-oriented programming, a blueprint for creating objects (a particular data structure), providing initial values for state (member variables)

and implementations of behavior (member functions or methods).

13 of 132

N-D Array Class

N-Dimensional array. In NumPy, this refers to the ndarray class, which represents a multidimensional, homogeneous array of fixed-size items, providing efficient storage and manipulation of numeric data.

14 of 132

Dimensional Array

0-D array - a single data point (scalar)

1-D array - a sequence of values (vector)

2-D array - a collection of 1-D sequences (matrix)

15 of 132

Array

A collection of elements identified by index or key, typically stored so that the position of each element can be computed from its index tuple by a mathematical formula.

16 of 132

NumPy Array (ndarrays)

The fundamental package for scientific computing with Python. It provides a high-performance multidimensional array object, and tools for working with these arrays.

17 of 132

Lists

A built-in Python data structure used to store collections of items. Lists are mutable, allowing for items to be added, removed, or changed.

18 of 132

Concatenation

The operation of joining two or more arrays or lists into a single one. In NumPy, concatenation can be done along any dimension.

19 of 132

NumPy Documentation

A collection of instructions about all the functions, methods, and classes within a module

and details on how to use them.

20 of 132

dtype

A data type object in NumPy that describes the kind of elements that are contained within an array, including types like integer, float, and complex numbers.

21 of 132

np.int

A NumPy data type that represents integers. It is equivalent to the C long type and varies in size depending on the platform.

22 of 132

np.int32

A NumPy data type that represents a 32-bit integer.

23 of 132

np.float16

A NumPy data type that represents a half-precision float, which is a 16-bit floating-point number.

24 of 132

np.complex64

A NumPy data type that represents a complex number with two 32-bit floating-point numbers, one each for the real and imaginary parts.

25 of 132

np.bool

A NumPy data type that represents boolean values (True or False).

26 of 132

np.str

A NumPy data type that represents strings.

27 of 132

shape Attribute

Returns a tuple representing the array's dimensions, providing the size of the array along each dimension. Rather than a method, it's not callable (doesn't need "()" at the end). The shapes of the arrays need to be compatible.

28 of 132

size Attribute

An NumPy arrays attribute that returns the total number of elements in the array, which is the product of the elements of the array's shape.

29 of 132

Indexing

The method by which elements of an array or list are accessed using their position number within the array. By adding numbers between square brackets, we can reference specific values of the array. Indexing in Python starts from zero.

30 of 132

Indices (Indexes)

The position numbers used to access specific elements within a data structure like an array or list.

31 of 132

'":" in Indexing

The colon (:) is used in indexing to specify a range of values in arrays. For example, array[start:stop] accesses elements from the 'start' index up to,

but not including, the 'stop' index.

32 of 132

Negative Indices

Negative indices mean traversing from the back. -1 represents the last item, -2 represents the second last, and so forth.

33 of 132

Assigning Values

The process of setting or changing the value of a specific element in an array or list by using its index.

34 of 132

Type Assigment

Refers to specifying the data type of the elements in an array at the time of its creation. Type assignment in Python is dynamic. Hence,

a variable's type can change based on what values we assign to it.

35 of 132

Type Casting

The method of converting an array from one dtype to another in NumPy. This can be done explicitly using the astype() function or implicitly during operations.

36 of 132

math Library

A Python library that provides access to mathematical functions for floating-point arithmetic, such as trigonometric functions, logarithmic functions, and more.

37 of 132

math.sqrt Function

A function in the math library of Python that calculates the square root of a specified number.

38 of 132

np.sqrt Function

The square root function computes the square root for every element of the array.

39 of 132

Broadcasting

A feature in NumPy that allows it to perform arithmetic operations on arrays of different shapes by temporarily 'broadcasting' the smaller array across the larger one.

40 of 132

Running over an Axis

Axis = 0 runs the function over every column. Axis = 1 runs the function over every row.

41 of 132

Slicing

A technique used to extract a subset of elements from an array or list using slice notation (start:stop:step).The slices consist of adjacent pieces of data and the slice can contain entire rows and columns of the original array, or just parts of them.

42 of 132

Stepwise Slicing

Specifying a 'step' in slicing allows skipping of elements within the slice range. For example, array[start:stop:step]

accesses elements within the 'start' and 'stop' range at intervals defined by 'step'.

43 of 132

Conditional Slicing

Accessing array elements using boolean expressions that specify which elements to include in the result based on their values.

44 of 132

Dimensions

Refers to the number of indices needed to specify an element's position within an array. For example, a 2D array has two dimensions.

45 of 132

squeeze Function

A function in NumPy that removes single-dimensional entries from the shape of an array, simplifying its structure.

46 of 132

np.empty Function

Creates a new array of a specified shape and dtype, without initializing entries, which means it contains random garbage values.

47 of 132

np.ones Function

Creates a new array of a specified shape and dtype, filled with ones.

48 of 132

np.zeros Function

Creates a new array of a specified shape and dtype, filled with zeros.

49 of 132

np.full Function

Creates a new array of a specified shape and dtype, filled with a specified fill value.

50 of 132

"_like" Functions

Functions in NumPy that create new arrays with the same shape and type as a given array.

51 of 132

np.empty_like Function

Creates a new array with the same shape and type as a given array but without initializing entries, leaving them with random values.

52 of 132

np.arange Functions

Returns evenly spaced values within a given interval.

53 of 132

Random Generators

Functions that generate random numbers from various statistical distributions.

54 of 132

np.random

A module in NumPy that provides a suite of functions for generating random numbers, samples, and distributions.

55 of 132

np.normal Method

A method in the np.random module used to draw random samples from a normal distribution.

56 of 132

np.integers Method

A method in the np.random module used to generate random integers between given low and high values.

57 of 132

np.choice Method

A method in the np.random module that generates a random sample from a given 1-D array or range.

58 of 132

Distributions

Describe how values are spread or distributed across a dataset. Different types of distributions can model different types of phenomena.

59 of 132

Poisson Distribution

Expresses the probability of a given number of events occurring in a fixed interval of time or space, assuming these events occur

with a known constant mean rate and independently of the time since the last event.

60 of 132

np.poisson Method

A method in the np.random module module that generates random samples from the Poisson distribution.

61 of 132

Binomial Distribution

Describes the number of successes in a fixed number of independent Bernoulli trials, each with the same probability of success.

62 of 132

np.binomial Method

A method in the np.random module that generates random samples from a binomial distribution.

63 of 132

Logistic Distribution

A continuous probability distribution used in logistic regression and can model the chance of a certain event occurring, such as pass/fail, win/lose, alive/dead.

64 of 132

np.logistic Method

A method in the np.random module that generates random samples from the logistic distribution.

65 of 132

Exponential Distribution

Describes the time between events in a Poisson point process, i.e., a process in which events occur continuously and independently at a constant average rate.

66 of 132

np.exponential Method

A method in the np.random module that generates random samples from an exponential distribution.

67 of 132

Geometric Distribution

A discrete distribution that models the number of trials needed to get the first success in repeated Bernoulli trials.

68 of 132

np.geometric Method

A method in the np.random module that generates random samples from the geometric distribution.

69 of 132

np.transpose Method

A method in NumPy used to permute the dimensions of an array, or to transpose a matrix.

70 of 132

Delimiter

A character or sequence of characters used to specify the boundary between separate, independent regions in plain text or other data streams (e.g., commas in CSV files).

71 of 132

np.load Method

Used to load arrays or pickled objects from .npy, .npz or pickled files.

72 of 132

np.savetxt Method

A method in NumPy used to save an array to a text file, with options to specify the delimiter and other formatting details.

73 of 132

np.genfromtxt Method

A function in NumPy used to load data from a text file, with the ability to handle missing values and flexible type conversion.

74 of 132

np.loadtxt Method

A function in NumPy used to load data from a text file, where each row in the text file must have the same number of values.

75 of 132

CSV

"Comma-Separated Values," a file format used to store tabular data in plain text, where each line corresponds to a data record and each record consists

of fields separated by commas.

76 of 132

np.array_equal Method

Checks if two arrays have the same shape and elements, returning True if they are equal.

77 of 132

np.savez Method

Used to save several arrays into a single file in uncompressed .npz format.

78 of 132

np.min Method

Used to return the minimum value from an array.

79 of 132

np.amin Method

An alias for the min method in NumPy, it performs the same operation and returns the minimum value in an array.

80 of 132

np.minimum Method

Used to compare two arrays and returns a new array containing the element-wise minima.

81 of 132

np.minimum.reduce Method

Applies the minimum operation along one axis of an array, reducing its dimension.

82 of 132

np.max Method

Used to return the maximum value from an array.

83 of 132

np.amax Method

An alias for the max method in NumPy, it performs the same operation and returns the maximum value in an array.

84 of 132

np.maximum.reduce Method

Applies the maximum operation along one axis of an array, reducing its dimension.

85 of 132

np.ptp Method

Returns the range (maximum - minimum) of values along an axis.

86 of 132

np.sort Method

Sorts an array, either along a specific axis or the entire array if no axis is specified.

87 of 132

Percentile

A value that is greater than the corresponding % of the dataset.

88 of 132

np.percentile Method

Used to compute the nth percentile of the given data (array elements) along the specified axis.

89 of 132

Quantile

A value that is greater than the corresponding part of the dataset.

90 of 132

np.quantile Method

Used to calculate the quantiles of the given data (array elements) along the specified axis.

91 of 132

np.median Method

Returns the median (middle value) of the data in the array along the specified axis.

92 of 132

np.average Method

Used to compute the weighted average of elements in an array along the specified axis.

93 of 132

np.mean Method

Calculates the arithmetic mean of elements across the specified axis of an array.

94 of 132

Varience

A statistical measure that represents the degree of spread in a dataset. The more spread out the data, the higher the variance.

95 of 132

np.var Method

Calculates the variance of the array elements along the specified axis.

96 of 132

Standart deviation

A statistic that measures the dispersion of a dataset relative to its mean and is calculated as the square root of the variance.

97 of 132

np.std Method

Computes the standard deviation of array elements along the specified axis.

98 of 132

Covarience

A measure used in statistics to determine the degree to which two variables change in tandem (i.e., co-vary).

99 of 132

np.cov Method

Computes the covariance matrix of two or more sets of variables.

100 of 132

Correlation

A statistical measure that indicates the extent to which two or more variables fluctuate in relation to each other.

101 of 132

np.corrcoef Method

Returns the correlation coefficients of a matrix representing the correlation between every pair of arrays.

102 of 132

Histogram

A graphical representation of the distribution of numerical data, where the data is divided into bins, and the frequency of data in each bin is represented.

103 of 132

np.histogram Method

Used to compute the histogram of a set of data along with the bin edges.

104 of 132

Preprocessing

Refers to the operations applied to raw data to make it suitable for further analysis, often involving normalization, scaling, handling missing data,

and encoding categorical variables.

105 of 132

NaN Values

Not A Number. Refers to missing or unpresentable values within a NumPy array.

106 of 132

np.isnan Method

Used to check element-wise for NaN in the array and returns a Boolean array indicating the presence of NaNs.

107 of 132

np.delete Method

Returns a new array with sub-arrays along an axis deleted from the original array.

108 of 132

Argument Functions

Functions that return indices, positions, or arguments where certain conditions are met, useful for data sorting and filtering.

109 of 132

np.argsort Method

Returns the indices that would sort an array along a specified axis.

110 of 132

np.argwhere Method

Finds the indices of array elements that are not zero, grouped by element.

111 of 132

Shuffling Data

A process where the order of data in an array is randomized, often used to ensure that models do not learn anything from the order of data.

Seeds don't work for shufling.

112 of 132

np.random.shuffle Method

Used to modify a sequence in-place by shuffling its contents.

113 of 132

Casting

Refers to changing an object from one data type to another, such as from an integer to a float in NumPy.

114 of 132

Stripping Data

The process of cleaning data by removing unwanted parts, such as leading/trailing spaces or invalid characters.

115 of 132

Stacking

A technique in NumPy that involves joining a sequence of arrays along a new axis.

116 of 132

np.unique Method

Finds the unique elements of an array and returns these unique elements, optionally returning associated indices or counts.

117 of 132

When to use NumPy?

118 of 132

Lists vs. Arrays

119 of 132

Given the following array, what will the result of the print function be?

4

120 of 132

Given the following array, what will the result of the print function be?

[ 4 5 6 ]

121 of 132

Given the following array, what will the result of the print function be?

[ 1, 2, 3, 2 ]

122 of 132

Given the following array, what will the result of the print function be?

[ [ 2 4 6 ]

[ 8 10 12 ]]

123 of 132

Broadcasting Rules

124 of 132

Given the following array, what will the result of the print function be?

[ [ 1 ]

[ 2 ] ]

125 of 132

Given the following array, what will the result of the print function be?

[ [ 1 ]

[ 2 ] ]

126 of 132

Given the following array, what will the result of the print function be?

[ [ 1 ] ]

127 of 132

Given the following array, what will the result of the print function be?

[ ]

128 of 132

Given the following array, what will the result of the print function be?

[ [ 4 3 0 ]

[ 3 6 4 ]

[ 1 1 0 ] ]

129 of 132

Given the following array, what will the result of the print function be?

[ False True False ]

130 of 132

Conditions

131 of 132

Given the following array, what will the result of the function be?

2.0

132 of 132

Given the following array, what will the result of the function be?

[ 2.5 3.5 4.5 ]