Software Tools for Earth System Sciences

Homework-II

due date : 07/12/2020 23:59

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Part 1 - Basic Math

• Look at Figure - “Math Eq”
• Write the solution

# aritmetic operators

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Part 2 - Assignment

• Create a new object with one value.
• hint : For example, use Part 1 for value, assign it in a new variable like
• Print your new object

#assignment arrow
#print()

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Part 3 - Class

• Print your name as a character string.
• Print your age as a numeric type.
• Print your age as a character type.
• Try to print your name as a numeric type. (?!)
• hint : kidding
• Check classes for all.
• What is the class of TRUE and NA ?

# print()
# " ... " 
# class()

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Part 4 - Vector

• Create a new vector which has 4 elements with numeric class.
• Print your vector with sorting. (decreasing = TRUE)
• Add a new character element at your vector.
• Now you must have 5 elemets. Learn the length of your vector.
• Check the class of your vector. (Numeric or Character ?)
• Now create another new vector, but now use sequence function.

# combine them
# my_new_vector <-
# sort
# length()
# seq()

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Part 5 - Matrice

• Create a new matrice with 4 rows and 5 colomns, using random variables.(random for the uniform distribution)
• Select the grid (or cell) located in 2nd row and 3rd coloms. (indexing)
• Change it with TRUE. (assigment)
• Check the dimension, structure, length and class of your matrice
• BONUS: Print values which is greater than or equal to 5 in your matrice.

# runif()
# matrix()
# indexing with []
# length()
# dim()
# str()
# class()
# which()
# >=

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Part 6 - Array

• Create a new vector which has 4 elements, character.
• Create a new matrice with 2 rows and 4 colomns, numeric.
• Combine them, and create a new array with 3 rows, 4 columns and 2 layers. (first row must be vector, second and third rows must be matrix for each layer)
• hint : you can use repetations function
• Try to add +2 for each values of 2nd layer of array.
• Check the dimension, structure, length and class of your array.

# vector()
# matrix()
# array()
# length()
# dim()
# str()
# length()
# class()

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Part 7 - Data Frame

• Create a new vector which has 4 elements, numerical.
• Create a new vector which has 4 elements, logical.
• Create a new matrice which has 4 rows and 2 columns, numerical.
• Create a data frame which has 4 rows and 4 columns with your numerical and logical vectors, and numreical matrice.
• Check the class and structure of your new data.
• Take the first column and assign it as a new variable. (It will look like a vector)
• hint : you can use $ symbol
• Plot this vector.
• BONUS: Find values which is lower than 20 and change them with NA. (now your vector has changed)
• Print and Plot this new vector.

# my_data <-
# class()
# my_data$
# plot()
# which()
# <20

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Emir