- What is the output?
# x is a 2 byte binary number
x = 0b0000000100000011
print("{0:d}".format(x))
Ans: 256 + 3 + 1 = 259.
- Which of these binary numbers is odd?
a. 0000000100000000
b. 0000000100000011
c. 0101110101101000
d. 0111010101010100
Ans: b, which is the only answer that ends with 1.
We know that
even + even == even
even + odd == odd
All the bits of a 16-byte binary value, other than the last bit, represent an
even power of two. Since the sum of even powers of
two is always even, the last bit determines whether
the entire number is even or odd.
- Interpret this binary number as (a) ASCII characters,
(b) packed decimal, (c) answers to a true/false quiz, (d) a 2 byte decimal number.
0100100001101001
Ans:
(a) The ASCII codes 01001000 and 01101001 represent
48 hex and 69 hex, respectively, which are the ascii codes
for H and i = Hi.
(b) The packed decimal value of the binary number is 4869.
(c) FTFFTFFFFTTFTFFT
(d) use the powers of 2 table:
214 + 211 + 27 + 26 + 22 + 21 =
16,384 + 2,048 + 64 + 32 + 8 + 1 = 18,537.
- Write a Python program to compute the bitwise and of the decimal values
13 and 6. Output the result in hex and decimal. Ans:
a = 13
b = 6
c = a & b
print("{0:02x} {1:d}".format(c, c))
# Output: 04 4
- Consider this code fragment:
value = 37.298
print(round(value, 2))
# Output:
37.3
How can we get it to print as 37.30?
Ans: Use the str format method:
value = 37.298
print("{0:6.2f}".format(value)
- What is a standalone method? List as many Python built in standalone methods as you can.
In particular, what do the standalone methods chr and
ord do?
Ans: See the Builtin Classes and Methods document.
Here are the some of the standalone methods that we listed during class today.
ord chr print type round len
input min max int str float
bool dict list
- Write a standalone method named get_greeting that inputs a name, for example
Larry, and returns a greeting using that name, for example Hello, Larry,
how are you? Test your method like this (traditional hardcoded test script):
greeting = get_greeting("Larry")
print(greeting)
# Ans:
# Define create_greeting in the module (Python file) greeter.py.
def create_greeting(the_name):
return "Hello, " + the_name + ", how are you?"
If the method is defined a different file named greeter.py, here are the traditional test statements
to test the get_greeting method:
from greeter import get_greeting
greeting = createGreeting("Larry")
print(greeting)
// or
from greeter import get_greeting
print(get_greeting("Larry"))