sample questions

a. Compiler

A compiler is a program that translates source code written in a high-level programming language into machine code. It allows a program to be executed by a computer.

b. Syntax Error

A syntax error occurs when code violates the grammatical rules of the programming language, preventing it from being parsed or executed.

c. Argument

An argument is a value or variable passed to a function when it is called, used by the function to perform its task.

What is the output of type(x) after the following statements are executed: x=3

x=[4]

x='5'

What is the value stored in x after: x = y[2]

'c'

What is the value stored in x after: x = y[:2]

['a', 'b']

What is the value stored in x after: x = y

['a', 'b', 'c', 'd']

Write a function which calculates the GC content of an input sequence

def gc_content(seq):
[tab] gc = sum(1 for base in seq if base in 'GCgc')
[tab] return (gc / len(seq)) * 100 if seq else 0

The following code contains Syntax Errors. Correct them, highlighting changes with underlined font

#!/usr/bin/env python3

import sys

with open(sys.argv[0], 'r') as instream, open(sys.argv[1], 'w') as outstream:

[tab]for line in instream

[tab] [tab] line = line.rstrip()

[tab] [tab] if 'this" in line:

[tab] [tab]outstream.print("Found a line with 'this':"{}.format(line))

[tab] outstream.print("Complete")

sys.exit()

#!/usr/bin/env python3

import sys

with open(sys.argv[1], 'r') as instream, open(sys.argv[2], 'w') as outstream:

for line in instream:

line = line.rstrip()

if "this" in line:

outstream.write("Found a line with 'this': {}\n".format(line))

outstream.write("Complete\n")

sys.exit()