Only
1st ~ 54th problems are counted for points.
(55th, 56th problems are not counted!)
# of correct answers : points
51-54 : 9
45-50 : 8
39-44 : 7
33-38 : 6
27-32 : 5
21-26 : 4
15-20 : 3
09-14 : 2
03-08 : 1
00-02 : 0
No deductions for writing an answer as 1 or 1.0 or 1.00 or 1.0e0
, ... )
No deductions for writing an answer as [ 1 2 3] as 1 2 3 and
[1;2;3] as
1
2
3
No deduction for omitting ans = or x
=
Fill
in the following blanks with the correct answers. If the answer gives a
Matlab error message, don't write down the
entire message, just fill in the blanks
with the word ERROR.
1.
>> 1 / 3
ans =
________0.33333333333333___if they used format long___or
____3.333333333333333e-001__if they used format long e___ (accept 0.3... with any number of 3's)
2.
>> 1\ 3
ans =
_______3________________
3.
>> 2^5
ans =
________32_______________ (exponentiation 2 raised to the fifth power)
4.
>> 2.0e1-3.0e0* 5.0e0
ans =
_______5________________ (operator precedence)
5.
>> (2.0e1-3.0e0)*5.0e0
ans =
________85_______________( parenthesis can change operator precedence)
6.
>> Inf + 1
ans =
________Inf__________Some students typed Inf +1 which would generate an ERROR so accept this answer.______
7.
>> Inf - 1
ans =
________Inf__________Some students typed Inf -1 which would generate an ERROR so accept this answer.______
8.
>> 1/Inf
ans =
_______0_______________
9.
>> Inf/Inf
ans =
_______NaN_______________
10.
>> 0 * Inf
ans =
_______NaN_______________
11.
>> (-1) * Inf
ans =
_________-Inf_____________
12.
>> Inf - Inf
ans =
________NaN______________
13.
>>1 / 0
ans =
_______Inf_______________
14.
>> -1 / 0
ans =
_______-Inf_______________
15.
>> i * i
ans =
__________-1____________ (Check your high school algebra book on
the
imaginary number i .)
16.
>> format short
>> 1+ 2*i
ans =
____1+2i__________________ (The general form of a complex number is "a+bi" where a and b are real numbers.)
17.
>> 1+2i
ans =
______1+2i________________ (no * is needed)
18.
>> ( 1+ 2i) + ( 3+ 4i)
ans =
______4 + 6i_________________ (addition of complex numbers)
19.
>> (1+ 2i ) * ( 3+ 4i)
ans =
______-5 + 10i_________________ (multiplication of complex numbers)
20.
>> (1+2i) / ( 3 + 4i)
ans =
_______.44 + .08i________________ (division of complex numbers)
21.
>> [ 1 2 3] ' (that's two
apostrophes not one
double-quote
character on your keyboard)
ans =
1
2
3
____________________
NOTE: Accept "Error" as a valid answer because this question had a typo.
22.
>> [ 1;2 ; 3] + [ 4; 5 ; 6]
ans =
5
7
9
_______________________
23.
>> [ 1; 2; 3] + [ 1 2 3]
ans =
___ERROR____________________ ( the two vectors are of the same length but not the same size)
24.
>> [ [ 1 ; 2 ; 3] , [ 1 2 3]' ] (yeah this is really a table type problem)
ans =
1 1
2 2
3 3
______________________
25.
>> x = -1 : 3
x =
___-1 0 1 2
3___________
26.
>> x = 1 : -3 : 7
x =
___ [ ]_____or "the empty
matrix"___________
27.
>> x = [ 1 1 1]
>> x = x + [1 1 1]
x =
___2 2 2______________
28.
>> x
x =
_____2 2 2____________ ( didn't we assign [ 1 1 1] to x???)
29.
>> y = [ x , 2 3 4]
y =
_____2 2 2 2
3
4_____
30.
>> x = linspace(-1, 1, 4)
x =
____-1 -.3333 .3333 1_________________ ( equally spaced vector starting at -1 ending at 1 with 4 values)
or -1 -1/3 1/3 1
31.
>> x = linspace(0, 5, 1000);
(don't
forget this semi-colon, it means suppress out to screen)
>> min(x)
ans =
______0________________ (of course!)
32.
>> max(x)
ans =
_______5_______________( same x as above)
33.
>> x = [ 1 3 5]
>> sum(x)
ans =
________9____________
34.
>> sum([1 ; 3 ; 5])
ans =
_________9___________
35.
>> z = [ 1 2 3; 4 5 6]
>> sum(z)
ans =
5 7 9
____________________ (sums values in columns for a table; nearly all Matlab functions work this way on tables)
36.
>> x = [ 1 3 6 12]
>> diff(x)
ans =
____2 3 6_________________ (diff(x) consecutive differences of values in x)
37.
>> x = [ 1 2 3]
>> mean([ 1 2 3])
ans =
_______2______________(arithmetic average =
(1+2+3)/3)
38.
>> x = [ 1 2 3 ]
>> median(x)
ans =
_________2_____________( median(x) = as many values above as are below)
39.
>> x = [ 1 2 3 4]
>> median(x)
ans =
________2.5_____________
40.
>> x = [ 1 2 3 4]
>> cumsum(x)
ans =
____1 3 6 10_________________ (cumlative sum)
41.
>> sqrt(-1)
ans =
______i________________
or
0 + i
42.
>> abs( 1+ 2i)
ans =
_______2.2361_______________ ( abs( a+bi) = sqrt(a*a +b*b) )
You should read the instructions for Part 6 and create a Matlab script file before you attempt the followings:
43. Before we run the script file, in the Matlab environment, enter the who command that lists all your variables,
>> who
List the variables:
___ans x y z _(any answer accepted )______________________________________________________
44. Now type the following,
>>clear
>>who
List the variables:
____________no variables______or empty_______________________________________________
45. Next type,
>> r = 1;
>>who
List the variables:
___________r___________(but not ans)_________________________________________________
>>r
46.
What is the value of r? ___1______
Use the "what" system command to make sure that you have correctly saved your lastname.m file.
>> what (this lists the .m and .mat files in your directory)
If you don't see the "lastname.m" file ask your TA for help before you proceed.
47. Run the script.
>> lastname
Write what is displayed on your screen:
x =
1
2
3
y =
0.8415 0.9093
0.1411
________________________________________________________________
48. Type
>>r
What is the value of r? ___4______
49. So, can running a script alter the value of a workspace variable? Yes
50. Again, type
>> who
List the variables in your workspace:
_________ans r x y____________________________________________
51. Compute the derivative of t3 with respect to t,
>> syms
t
Fill in the blank with Matlab code to call
the diff
function to compute the second derivative of t3. You
must use
the diff function.
>> solution = ____diff( t^3,t,2)_or diff(t.^3,t,2) or diff(t^3,2) or diff(t.^3,2) (solution should give 6t )
52. Write the result of executing the following code,
>> syms y
>> limit( sin(y)/y , y , 0)
__________1_________________
53. Write the result of executing the following code,
>> syms z
>> diff( sin(z), z , 4)
_______sin(z)____________________
54. Find in the course syllabus: Find the grade range(in points for an A- grade for CS101)
__________625-649______________
55. Click the "Staff " hyper-link: What is the email address of your lab TA?
56. Follow the instructions in Part 9.
Then, obtain the signature of your TA and submit this answer sheet to
your lab
TA.
__________any TA signature_____________________________________