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Master R Programming

95

TOPICS

12

SECTIONS

SKILL MASTERY

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95 skills · 427 questions

All Skills

All

95 core skills 100% total weight

01

apply-Family Functions

02

Performance Pitfalls

03

Vectorization Performance

04

If/Else & Else-If Chains

05

Nested Conditionals

06

07

08

09

Vectorization vs. Loops

10

11

12

13

Subsetting Data Frames

14

15

apply/lapply/sapply

16

Converting Data Structures

17

18

19

Creating Vectors

20

Handling NA Values

21

Vector Indexing

22

which() & Logical Subsetting

23

browser() & debug()

24

Errors, Warnings & Messages

25

print() & str()

26

27

stopifnot() & Assertions

28

Testing with Edge Cases

29

30

Default & Named Arguments

31

Defining Functions

32

Function Documentation

33

Scoping & Environments

34

Vectorized Functions

35

Avoiding Global State

36

Code Organization

37

Package Structure

38

39

Installing & Loading Packages

40

41

42

43

Working Directory & Paths

44

45

Resolving Merge Conflicts

46

Using .gitignore

47

48

Reading CSV Files

49

Reading Excel Files

50

Writing CSV Files

51

52

group_by() & summarize()

53

Joining Data Frames

54

mutate() & Recoding

55

select() & rename()

56

Building ggplots

57

Creating Common Plots

58

Customizing ggplot

59

60

Handling Missing Values in Reshaping

61

pivot_longer() & pivot_wider()

62

separate() & unite()

63

Extracting Model Outputs

64

65

Linear Models (lm)

66

Logistic Regression (glm)

67

Random Sampling

68

set.seed() for Reproducibility

69

Simulation & Variability

70

Communicating Limitations

71

Explaining Analysis Steps

72

Stating Assumptions

73

Naming & Formatting

74

Readable Pipelines

75

76

Style Conventions

77

78

79

80

Type Conversion

81

82

Arithmetic Operators & Precedence

83

Comparison & Logical Operators

84

85

Vectorized vs. Short-Circuit Operators

86

Immutability vs. Reassignment

87

Naming Conventions

88

Variable Assignment (<- vs. =)

89

Vectorized Operations

90

Date/POSIXct Objects

91

lubridate Functions

92

Parsing Dates & Time Zones

93

Basic String Functions

94

Cleaning Text Data

95

Regular Expressions