Module 3

Looping through text

Processing each character of a string.

One character at a time

You can loop through a string to process each character. This is extremely useful in bioinformatics.

Python

for base in "ATGC":
    print(base)

→ A T G C

Each character of the string is visited in order. You can count, filter, or transform each one.

Python

seq = "ATGC"
count = 0
for base in seq:
    count = count + 1
print(count)

→ 4

Your task

Count with a loop