SAFCODE

Test Your Programming Skills with Safcode!

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Here is all important interview / exams questions.
Student doing practice apptitude test on safcode platform.
Instruction: "Total Number of Questions: 20
Each question carry 10 mark , no negative marking"

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Quiz Start

1. The __________ function is used to group data frame. summerize()
group_by()
matrix()
List()

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2. The lapply() function takes ___________, ____________ and __________ as input. List, Vector and Data Frame
None of them
Data Frame, Array
Array, List, Matrix

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3. __________ are useful when you want to display proportional makeup of a sample in presentations. Pie charts
Scatter charts
Bubble charts
Bar charts

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4. _____________ is an open source R package that provides an elegant and powerful Web framework for building Web applications. Shiny
Dash
Ggplot2
Leaflet

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5. ____________ is the raw collection of records, contents and images. Data frame
Data
Tables
Matrix

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6. How are null entries in a data frame denoted in R? None of these
na
NaN
n/a

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7. Response variable is represented on ___________ x-axis
both x-axis and y-axis
y-axis
none of them

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8. Histograms are good to display the _________ of the data. Mode
Quartile
Median
Mean

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9. Which function is used to add labels to the graph in the ggplot() function. label()
All of them
lab()
labs()

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10. Response variable is represented on _______________ no axis
both x-axis and y-axis
x-axis
y-axis

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11. What is the memory limit in R? 4TB
2TB
6TB
8TB

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12. What is the function used to read CSV files into R? csv()
read_csv()
read()
readfile()

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13. R is an__________programming language? None of above
Close Source
Open Source
GPL

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14. ___________ returns a character vector of the same length and with the same attributes as x. regexp()
paste()
grep()
gsub()

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15. __________ is used to plot scatter plot of two variables in accordance with the third variable. None of these
Coplot
Heatmap
Violin graph

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16. The __________ function is used to select data by its column names. retrieve()
all of them
fetch()
select()

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17. Which function is used to add regression line to the scatter plot. None of them
smooth()
abline()
abs_line()

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18. The function that is used to extract or replace substrings in a character vector in ____________ substr()
sub_string()
string()
subchar()

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19. OOP stands for? Option Object Programming
Orange Oriented Pixels
Object Oriented Programming
Object of Program

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20. _____________ is not a type of operator in R. Mathematical
Relational
Assignment
Logical

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