R Notebook

kkk = 980

Variable Type

# number variable
num_var = 10
num_var2 = 20.5

# char variable -> letter, sentence
char_var = "This is a char variable"
char_var2 ="এই টা একটা char variable "
char_var3 = 'this is another char variable'

char_var2

[1] "এই টা একটা char variable "

# logical variable 
logic1 = TRUE
logic2 = FALSE

char_var2

[1] "এই টা একটা char variable "

# vector
num_vec = c( 1, 5 ,10, 50, 65 )
fish_vec = c( "hilsha", "Ruhi", "Telapia" )
fish_vec

[1] "hilsha"  "Ruhi"    "Telapia"

kjsdjkn 

[1] 100

kkk 

[1] 980

apple = 1000
kjsdjkn = 100

print(char_var2)
print.noquote(char_var2)

all_type_vec = c("Char", 19, 10, -57, FALSE, "jhksdf")
all_type_vec

[1] "Char"   "19"     "10"     "-57"    "FALSE"  "jhksdf"

all_type_vec = 100

Arithmetic Operation

a = 10
b = 5

# Add
add = a+b

#minus
sub = a - b

#Division
div = a/b

#Multiplication
mult = a*b

# power 
p = a^2

#Modulo
m = a %% b
m2 = a %% 3

cat(add, sub, div, mult, p, m, m2)

15 5 2 50 100 0 1

Combined calculation

c = (10 +- (5-2) * 20 + (20-10))*10
c

[1] -400

String

?paste

Concatenation or Merge

var1 = "This is a variable."
var2 = "I am another variable."

combined = paste(var1, var2, var1, var2, sep = " - ")
combined

[1] "This is a variable. - I am another variable. - This is a variable. - I am another variable."

var1 = "GTAC"
var2 = "ATGCA"
paste(var1, var2, sep="")

[1] "GTACATGCA"

Segment

var = "GTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCA"

x3 = substr(var, start = 12, stop = 16) # 12 13 14 15 16
x1 = substr(var, start = 10, stop = 20)
x2 = substr(var, start = 12, stop = 25)

x = c(x1, x2, x3)

Length

nchar(var)

[1] 63

nchar(x)

[1] 11 14  5

Pattern Exists?

gene_seq = "GTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCA"
pattern1 = "ATGCCCCA"
pattern2 = "TGCAG"

grepl(pattern1, gene_seq)

[1] FALSE

grepl(pattern2, gene_seq)

[1] TRUE

Pattern Matching

gene_seq = "GTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCAGTACATGCA"
pattern1 = "ATGCCCCA"
pattern2 = "TGCAG"

matches = gregexpr(pattern2, gene_seq)
matches = unlist(matches)
matches

[1]  6 15 24 33 42 51

matches = gregexpr(pattern1, gene_seq)
matches = unlist(matches)
matches

[1] -1

Split

gene_seq = "GTACATGCAGT,ACATGCAGTACA,TGCAGTACATGCA,GTACA,TGCAGTAC,ATGCAGTACAT,GCA"
gene_vec = strsplit(gene_seq, split = ",")
gene_vec

[[1]]
[1] "GTACATGCAGT"   "ACATGCAGTACA"  "TGCAGTACATGCA" "GTACA"         "TGCAGTAC"      "ATGCAGTACAT"   "GCA"          

gene_seq = "GTACATGCAGT ACATGCAGTACA TGCAGTACATGCA GTACA TGCAGTAC ATGCAGTACAT GCA"
gene_vec = strsplit(gene_seq, split = " ")
gene_vec

[[1]]
[1] "GTACATGCAGT"   "ACATGCAGTACA"  "TGCAGTACATGCA" "GTACA"         "TGCAGTAC"      "ATGCAGTACAT"   "GCA"          

Reverse

library(stringi)
gene_seq = "This is a cat"

rev_gene_seq = stri_reverse(gene_seq)
rev_gene_seq

[1] "tac a si sihT"