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+<code>
+% ==================================================================
+% A few more matlab basics
+% format: change appearance of output
+% 'format long' makes matlab print in full (16 digit) precision
+pi
+ans =
+.1416
+format long
+pi
+ans =
+.141592653589793
+% Special numbers: inf, NaN, i, j
+% inf is infinity, for example 1 divided by 0
+/0
+ans =
+   Inf
+% NaN is 'not a number', for example 0 divided by 0, which is undefined
+/0
+ans =
+   NaN
+% i and j are the unit imaginary numbers, the square root of -1
+i
+ans =
+.000000000000000 + 1.000000000000000i
+j
+ans =
+.000000000000000 + 1.000000000000000i
+i^2
+ans =
+    -1
+% most common functions have extensions to the set of complex numbers
+cos(2+3*i)
+ans =
+ -4.189625690968807 - 9.109227893755337i
+% caution: if you use a function name for a variable name, you won't be able
+% to access the function until you clear the variable
+rand = rand()
+rand =
+.090750827467831
+rand()
+ans =
+.090750827467831
+rand()
+ans =
+.090750827467831
+rand()
+ans =
+.090750827467831
+% hmmm, why do I keep getting the same random number?
+% because you're access a variable named 'rand' and not the function 'rand()", silly!
+whos
+  Name          Size            Bytes  Class     Attributes
+  ans           1x1                16  double    complex
+  rand          1x1                 8  double
+  x         10000x1             80000  double
+% you need to run 'clear rand' to release the variable
+clear rand
+whos
+  Name          Size            Bytes  Class     Attributes
+  ans           1x6                12  char
+  x         10000x1             80000  double
+% now you can access the function again
+rand()
+ans =
+.546980919566268
+rand()
+ans =
+.895124242734885
+% characters: one last data type, along with double, int32, uint32, ..., and logical
+% you can assign a set fo characters to a variable as follows
+f = 'foo'
+f =
+foo
+whos
+  Name          Size            Bytes  Class     Attributes
+  ans           1x1                 8  double
+  f             1x3                 6  char
+  x         10000x1             80000  double
+% ====================================================================
+% Vectors and matrices
+% Construct a row vector by explicitly listing its elements, separated by commas
+x = [4, 5, 9]
+x =
+     5     9
+% Construct a column vector by explicitly listing its elements, separated by semicolons
+x = [4; 5; 9]
+x =
+% To access an element (component) of the vector, use parentheses
+% x(i) accesses ith component of x
+x(1)
+ans =
+x(2)
+ans =
+x(3)
+ans =
+x(4)
+{Index exceeds matrix dimensions.} % error message
+% Transpose: the transpose operator ' (apostrophe) turns a row vector into a col vec
+x
+x =
+     5     9
+y = x'
+y =
+y'
+ans =
+     5     9
+% Matlab colon syntax
+% m:n means m through n by intervals of 1
+:4
+ans =
+     2     3     4
+:10
+ans =
+     2     3     4     5     6     7     8     9    10
+% x:inc:y means x through y by steps of inc
+:0.2:1   % 0 through 1 by steps of 0.2
+ans =
+    0.2000    0.4000    0.6000    0.8000    1.0000
+% use this functionality to produce plot of sin(x) for 0 <= x < pi
+x = 0:0.1:pi;
+size(x)
+ans =
+    32
+plot(x,sin(x),'r-')
+plot(x,sin(x),'r.-')
+% linspace: another way to get a vector of uniformly spaced points
+x = linspace(0,pi,100);   % 100 uniformly distributed points btwn 0 and pi
+size(x)
+ans =
+   100
+plot(x,sin(x),'r.-')
+x(1)
+ans =
+x(2)
+ans =
+.0317
+x(3)
+ans =
+.0635
+x(4)
+ans =
+.0952
+% subindexing: how to extract a subset of the components of a vector
+% observe that x is a vector of dimension 100 and look at the values of
+% its first four components
+size(x)
+ans =
+   100
+x(1)
+ans =
+x(2)
+ans =
+.0317
+x(3)
+ans =
+.0635
+x(4)
+ans =
+.0952
+% recall that 1:4 means the vector [1, 2, 3, 4]
+:4
+ans =
+     2     3     4
+% extract components 1,2,3,4 of x using syntax x(1:4)
+x(1:4)
+ans =
+    0.0317    0.0635    0.0952
+% extract components 1,2,3,4 of x using syntax x([1 2 3 4]), will give same thing
+x([1 2 3 4])
+ans =
+    0.0317    0.0635    0.0952
+% Some more demonstrations of subindexing
+x = 11:15
+x =
+    12    13    14    15
+x(1:3)
+ans =
+    12    13
+x(3:5)
+ans =
+    14    15
+x([5 4 3 2 1])
+ans =
+    14    13    12    11
+x(5:-1:1)
+ans =
+    14    13    12    11
+x(randi(5,1,5))
+ans =
+    14    14    13    12
+% Vector arithmetic: vectors add elementwise
+x = [ 4 5 9]
+x =
+     5     9
+y = [1 2 0]
+y =
+     2     0
+x + y
+ans =
+     7     9
+% scalar multiplication
+x
+x =
+     5     9
+*x
+ans =
+    10    18
+% norm: measures the length of a vector
+norm(x)
+ans =
+.0454
+x
+x =
+     5     9
+sqrt(4^2 + 5^2 + 9^2)
+ans =
+.0454
+% Matrices
+% create a matrix literally
+A = [4, 5, 9 ; 3, 2, 1 ; 0 , 6,4]
+A =
+     5     9
+     2     1
+     6     4
+% Accessing components
+A = [4, 5, 9 ; 3, 2, 1 ; 0 , 6,4]
+A =
+     5     9
+     2     1
+     6     4
+% A(i,j) gets elem in ith row and jth col
+A(1,1)
+ans =
+A(1,2)
+ans =
+A(3,1)
+ans =
+% you can also assign a new number into a matrix element
+A(3,1) = 99
+A =
+     5     9
+     2     1
+     6     4
+% indexing with colons
+% A(:,j) returns jth column
+A(:,1)
+ans =
+A(:,2)
+ans =
+A(:,3)
+ans =
+A
+A =
+     5     9
+     2     1
+     6     4
+% A(i,:) returns ith row
+A(1,:)
+ans =
+     5     9
+A(2,:)
+ans =
+     2     1
+A(3,:)
+ans =
+     6     4
+% A(i,m:n) returns ith row elements m through n
+A =
+     5     9
+     2     1
+     6     4
+A(1,:)
+ans =
+     5     9
+A(1,2:3)
+ans =
+     9
+</code>

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