Merge branch 'adambard-master' into r-spanish

1 files changed, 25 insertions, 7 deletions

diff --git a/matlab.html.markdown b/matlab.html.markdown
index 0cbc6f57..ddc0cb40 100644
--- a/matlab.html.markdown
+++ b/matlab.html.markdown
@@ -1,10 +1,11 @@
 ---
 language: Matlab
+filename: learnmatlab.mat
 contributors:
     - ["mendozao", "http://github.com/mendozao"]
     - ["jamesscottbrown", "http://jamesscottbrown.com"]
     - ["Colton Kohnke", "http://github.com/voltnor"]
-
+    - ["Claudson Martins", "http://github.com/claudsonm"]
 ---
 
 MATLAB stands for MATrix LABoratory. It is a powerful numerical computing language commonly used in engineering and mathematics.
@@ -14,6 +15,7 @@ If you have any feedback please feel free to reach me at
 [osvaldo.t.mendoza@gmail.com](mailto:osvaldo.t.mendoza@gmail.com).
 
 ```matlab
+%% Code sections start with two percent signs. Section titles go on the same line.
 % Comments start with a percent sign.
 
 %{
@@ -71,7 +73,7 @@ c = exp(a)*sin(pi/2) % c = 7.3891
 
 % Calling functions can be done in either of two ways:
 % Standard function syntax:
-load('myFile.mat', 'y') % arguments within parantheses, spererated by commas
+load('myFile.mat', 'y') % arguments within parentheses, separated by commas
 % Command syntax:
 load myFile.mat y 	% no parentheses, and spaces instead of commas
 % Note the lack of quote marks in command form: inputs are always passed as
@@ -122,6 +124,7 @@ x(2:end) % ans = 32 53 7 1
 x = [4; 32; 53; 7; 1] % Column vector
 
 x = [1:10] % x = 1 2 3 4 5 6 7 8 9 10
+x = [1:2:10] % Increment by 2, i.e. x = 1 3 5 7 9
 
 % Matrices
 A = [1 2 3; 4 5 6; 7 8 9]
@@ -204,6 +207,8 @@ transpose(A) % Transpose the matrix, which is the same as:
 A one
 ctranspose(A) % Hermitian transpose the matrix
 % (the transpose, followed by taking complex conjugate of each element)
+A' % Concise version of complex transpose
+A.' % Concise version of transpose (without taking complex conjugate)
 
 
 
@@ -253,6 +258,8 @@ axis equal % Set aspect ratio so data units are the same in every direction
 
 scatter(x, y); % Scatter-plot
 hist(x); % Histogram
+stem(x); % Plot values as stems, useful for displaying discrete data
+bar(x); % Plot bar graph
 
 z = sin(x);
 plot3(x,y,z); % 3D line plot
@@ -261,7 +268,7 @@ pcolor(A) % Heat-map of matrix: plot as grid of rectangles, coloured by value
 contour(A) % Contour plot of matrix
 mesh(A) % Plot as a mesh surface
 
-h = figure	% Create new figure object, with handle f
+h = figure % Create new figure object, with handle h
 figure(h) % Makes the figure corresponding to handle h the current figure
 close(h) % close figure with handle h
 close all % close all open figure windows
@@ -272,7 +279,7 @@ clf clear % clear current figure window, and reset most figure properties
 
 % Properties can be set and changed through a figure handle.
 % You can save a handle to a figure when you create it.
-% The function gcf returns a handle to the current figure
+% The function get returns a handle to the current figure
 h = plot(x, y); % you can save a handle to a figure when you create it
 set(h, 'Color', 'r')
 % 'y' yellow; 'm' magenta, 'c' cyan, 'r' red, 'g' green, 'b' blue, 'w' white, 'k' black
@@ -329,7 +336,7 @@ double_input(6) % ans = 12
 % anonymous function. Useful when quickly defining a function to pass to
 % another function (eg. plot with fplot, evaluate an indefinite integral
 % with quad, find roots with fzero, or find minimum with fminsearch).
-% Example that returns the square of it's input, assigned to to the handle sqr:
+% Example that returns the square of it's input, assigned to the handle sqr:
 sqr = @(x) x.^2;
 sqr(10) % ans = 100
 doc function_handle % find out more
@@ -399,7 +406,7 @@ exp(x)
 sqrt(x)
 log(x)
 log10(x)
-abs(x)
+abs(x) %If x is complex, returns magnitude
 min(x)
 max(x)
 ceil(x)
@@ -410,6 +417,14 @@ rand % Uniformly distributed pseudorandom numbers
 randi % Uniformly distributed pseudorandom integers
 randn % Normally distributed pseudorandom numbers
 
+%Complex math operations
+abs(x) 	 % Magnitude of complex variable x
+phase(x) % Phase (or angle) of complex variable x
+real(x)  % Returns the real part of x (i.e returns a if x = a +jb)
+imag(x)  % Returns the imaginary part of x (i.e returns b if x = a+jb)
+conj(x)  % Returns the complex conjugate 
+
+
 % Common constants
 pi
 NaN
@@ -459,11 +474,14 @@ length  % length of a vector
 sort    % sort in ascending order
 sum     % sum of elements
 prod    % product of elements
-mode	% modal value
+mode    % modal value
 median  % median value
 mean    % mean value
 std     % standard deviation
 perms(x) % list all permutations of elements of x
+find(x) % Finds all non-zero elements of x and returns their indexes, can use comparison operators, 
+        % i.e. find( x == 3 ) returns indexes of elements that are equal to 3
+        % i.e. find( x >= 3 ) returns indexes of elements greater than or equal to 3
 
 
 % Classes