YouTipR Func Match
# R match() Function - Element Matching
[ R Language Examples](#)
The R match() function is used to find the first occurrence position of elements from one vector in another vector.
match() is similar to the %in% operator, but returns positions instead of logical values.
The syntax format of the match() function is as follows:
match(x, table, nomatch = NA_integer_)
**Parameter Description:**
* **x** The vector of elements to look up.
* **table** The target vector to be searched.
* **nomatch** The value returned when matching fails, default is NA.
## Example
# Find element positions
fruits <-c("apple", "banana", "Orange", "Grape", "Watermelon")
wanted <-c("banana", "Watermelon", "Lemon")
# Find positions of elements in wanted within fruits
positions <-match(wanted, fruits)
print("Match Result:")
print(positions)
# Corresponding lookup: get actual values using positions
print("Matched Fruit:")
print(fruits[positions[!is.na(positions)]])
Execute the above code, the output result is:
"Match Result:" 2 5 NA "Matched Fruit:" "banana" "Watermelon"
match() is commonly used to reorder another data based on one vector:
## Example
# Student grade table
student_names <-c("Zhang San", "Li Si", "Wang Wu", "Zhao Liu")
scores <-c(88, 92, 76, 85)
names(scores)<- student_names
# Arrange grades in specific order
wanted_order <-c("Wang Wu", "Zhao Liu", "Zhang San", "Li Si")
idx <-match(wanted_order, names(scores))
print("Scores Arranged in Specified Order:")
print(scores)
Execute the above code, the output result is:
"Scores Arranged in Specified Order:"Wang Wu Zhao Liu Zhang San Li Si 76 85 88 92
[ R Language Examples](#)