sept_11_2014_be1500
TRANSCRIPT
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diary onsomeArray = [7 21 63 1 8 17]
someArray =
7 21 63 1 8 17
someArray', size
ans =
7 21 63 1 8 17
{Error using sizeNot enough input arguments.}someArray', size(someArray)
ans =
7 21 63 1 8 17
ans =
1 6
tsomeArray = someArray'
tsomeArray =
7 21 63 1 8 17
someotherArray = [1:20]
someotherArray =
Columns 1 through 18
1 2 3 4 5 6 7 8 9 10 11 12 1314 15 16 17 18
Columns 19 through 20
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19 20
size(someOtherArray){Undefined function or variable 'someOtherArray'.}size(someotherArray)
ans =
1 20
someotherArray =someotherArray = |{Error: Expression or statement is incomplete or incorrect.}someotherArray[20:-1:1]someotherArray[20:-1:1] |{Error: Unbalanced or unexpected parenthesis or bracket.}clcmyArray = [0:2:20]
myArray =
0 2 4 6 8 10 12 14 16 18 20
myArray(3) = []
myArray =
0 2 6 8 10 12 14 16 18 20
size(myAray){Undefined function or variable 'myAray'.}
size(myArray)
ans =
1 10
myZeroArray = zeros(1,2)
myZeroArray =
0 0
myZeroArray = zeros(1,20)
myZeroArray =
Columns 1 through 19
0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0
Column 20
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0
clcmyOneArray = ones(1,2)
myOneArray =
1 1
myOneArray = ones(1,20)
myOneArray =
Columns 1 through 19
1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1
Column 20
1
clcmyFirstLinspace = linspace(0,10,5)
myFirstLinspace =
0 2.5000 5.0000 7.5000 10.0000
% Define linspace: linspace is a mathematical built in function in Matlab whichcreates an array with n elements equally spaced from a to b.% Execution command: >>linspace(a,b,n)% there are (n-1) subintervals, we have 4 subintervals.% so matlab calculated (a,b)/(n-1)mySecondLinspace = linspace(1,10,5)
mySecondLinspace =
1.0000 3.2500 5.5000 7.7500 10.0000
% (b-a)/(n-1) is the real calculation behind the scenes% in mySecondLinspace the increment is 2.25myThirdLinspace = linspace(2,25,7)
myThirdLinspace =
2.0000 5.8333 9.6667 13.5000 17.3333 21.1667 25.0000
myThirdLinspace = linspace(2,20,7)
myThirdLinspace =
2 5 8 11 14 17 20
% the number of points generated is 7 and the number of subintervals is 6clear all; clcmyFirstString = Hello WorldmyFirstString = Hello World |{Error: Unexpected MATLAB expression.
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}myFirstString = Hello World! !myFirstString = Hello World! ! |{Error: Unexpected MATLAB expression.}myFirstString = 'Hello World! !'
myFirstString =
Hello World! !
% Strings: A sequence of characters ( elements that represent numbers, letter symbols, alphabets, etc.)mySecondString = 'a'
mySecondString =
a
myThirdString = 'a '
myThirdString =
a
myFourthString = 'a b c d'
myFourthString =
a b c d
myFifthString = 'five'
myFifthString =
five
size(myFifthString)
ans =
1 4
myFifthString(3)
ans =
v
mySixthString = " doesn't work"mySixthString = " doesn't work" |{Error: The input character is not valid in MATLAB statements or expressions.}% apostophes work instead of quotationsclcclear allmyFirstArrayOperation = [1 2 4 6]
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myFirstArrayOperation =
1 2 4 6
mySecondArrayOperation = [1 2 4 6]
mySecondArrayOperation =
1 2 4 6
mySecondArrayOperation = [3 5 9 11]
mySecondArrayOperation =
3 5 9 11
mySecondArrayOperation + myFirstArrayOperation
ans =
4 7 13 17
clcmyFirstArrayOperation - mySecondArrayOperation
ans =
-2 -3 -5 -5
clcourArray1 = [1 2 3];ourArray2 = [4 5 6];ourArray1*ourArray2{Error using * Inner matrix dimensions must agree.}
%we need to transpose one of the arraysourArray1*ourArray2'
ans =
32
% to transpose an array add an " ' " to the end of the array you wish to transpose% [4x2]*[2x3] = [4x3]%Define dot product: The dot product of two n-dimensional arrays is calculated by (sumation notation) U(i) x V(i)% >> ourArray1 = [1 2 3]
% >> ourArray2 = [2 5 6]% ourArray1 * ourArray2' = 1x4 + 2x5 + 3x6 = 4 + 10 + 18 = 32ourArray1 .* ourArray2
ans =
4 10 18
% calculation of element by element dot operatorourArray1 / ourArray2
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ans =
0.4156
ourArray1 ./ ourArray2
ans =
0.2500 0.4000 0.5000
ourArray1 / ourArray2'{Error using / Matrix dimensions must agree.}ourArray1 ./ ourArray2'{Error using ./ Matrix dimensions must agree.}clear all; clc% define matrix: A matrix is a data structure which has dimensions MxN where M and N cannot equal 1
myFirstMatrix = [3 4 6; 7 8 9]
myFirstMatrix =
3 4 6 7 8 9
numel(myFirstMatrix)
ans =
6
size(myFirstMatrixsize(myFirstMatrix |{Error: Expression or statement is incorrect--possibly unbalanced (, {, or [.}size(myFirstMatrix)
ans =
2 3
myFirstMatrix
myFirstMatrix =
3 4 6 7 8 9
myFirstMatrix(2,2) = 99
myFirstMatrix =
3 4 6
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7 99 9
myFirstMatrix(2,2) = []{Subscripted assignment dimension mismatch.}myZeroMatrix = zeros(2,3)
myZeroMatrix =
0 0 0 0 0 0
myZeroMatrix = ones(2,3)
myZeroMatrix =
1 1 1 1 1 1
myFirstMatrix
myFirstMatrix =
3 4 6
7 99 9
myFirstMatrix(:,2)
ans =
4 99
myFirstMatrix(1,:)
ans =
3 4 6
myFirstMatrix(2,:)
ans =
7 99 9
myFirstMatrix(:,3)
ans =
6
9
myFirstMatrix(:,3) = []
myFirstMatrix =
3 4 7 99
myFirstMatrix(1,3) = [6]
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myFirstMatrix =
3 4 6 7 99 0
myFirstMatrix(2,3) = [9]
myFirstMatrix =
3 4 6 7 99 9
anArray = [1:10]
anArray =
1 2 3 4 5 6 7 8 9 10
anArray = anArray*10
anArray =
10 20 30 40 50 60 70 80 90 100
anArray(3:5) = []
anArray =
10 20 60 70 80 90 100
% deleting elements: We can delete single elements from an array, as well as subarrays% We can delete single arrays from matriciesclcclear all
clcnewMatrix = magic(3)
newMatrix =
8 1 6 3 5 7 4 9 2
newMatrix(1:2,:)
ans =
8 1 6 3 5 7
clcnewMagicMatirx = magic(5)
newMagicMatirx =
17 24 1 8 15 23 5 7 14 16
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4 6 13 20 22 10 12 19 21 3 11 18 25 2 9
newMagicMartrix(2:4,:){Undefined variable newMagicMartrix.}newMagicMatrix(2:4,:){Undefined variable newMagicMatrix.}newMagicMatirx
newMagicMatirx =
17 24 1 8 15 23 5 7 14 16 4 6 13 20 22 10 12 19 21 3 11 18 25 2 9
newMagicMatrix(2:4,:){Undefined variable newMagicMatrix.}newMagicMatirx(2:4,:)
ans =
23 5 7 14 16 4 6 13 20 22 10 12 19 21 3
aMatrix = ones(5)
aMatrix =
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
bMatrix = [1:5;6:10;11:15;16:20;21:25]
bMatrix =
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
aMatrix + bMatrix
ans =
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
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aMatrix - bMatrix
ans =
0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 -11 -12 -13 -14 -15 -16 -17 -18 -19 -20 -21 -22 -23 -24
bMatrix = [1:5;6:10;11:15;16:20;21:25]
bMatrix =
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
cMatrix = [2 3 4; 5 7 1]
cMatrix =
2 3 4 5 7 1
dMatrix = [11 12 4; 5 0 22]
dMatrix =
11 12 4 5 0 22
cMatrix * bMatrix{Error using * Inner matrix dimensions must agree.}cMatrix * bMatrix'{Error using * Inner matrix dimensions must agree.}cMatrix * dMatrix'
ans =
74 98
143 47
cMatrix .* dMatrix
ans =
22 36 16 25 0 22
fiveByfive = magic(5)
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fiveByfive =
17 24 1 8 15 23 5 7 14 16 4 6 13 20 22 10 12 19 21 3 11 18 25 2 9
diag(fiveByfive)
ans =
17 5 13 21 9
clceye(5)
ans =
1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1
diag(eye(5))
ans =
1 1 1
1 1
clclastArray = [1:5]
lastArray =
1 2 3 4 5
lastArray1 = [6:10]
lastArray1 =
6 7 8 9 10
conArray = [lastArray, lastArray1]
conArray =
1 2 3 4 5 6 7 8 9 10
diary off