MATLAB: Matlab-basic

MATLAB

hi,

does matlab program inside a if loop always executed sequentially ?

Best Answer

No, the Just In Time (JIT) compiler can end up reordering some portions of the code.

See also this recent question: http://www.mathworks.com/matlabcentral/answers/21511-execution-order

Related Solutions

MATLAB: Graph (some basic)

prompt = 'What is the value of Area, A? ';
A = input(prompt)
prompt = 'What is the value of Heat Transfer Coefficient, h? ';
h = input(prompt)
prompt = 'What is the value of Temperature of System, Ts? ';
Ts = input(prompt)
prompt = 'What is the value of Temperature of Surroundings, Tf? ';
Tf = input(prompt)
prompt = 'What is the value of mass, m? ';
m = input(prompt)
prompt = 'What is the value of Heat Capacity, c? ';
c = input(prompt)
prompt = 'What is the value of time interval, dt? ';
dt = input(prompt)
prompt = 'What is the value of time at the end, tend? ';
tend = input(prompt)
 q2 = 150;
 
 tvals = 0 : dt : tend;
 num_t = length(tvals);
 Tn = zeros(1, num_t);
 for tidx = 1 : num_t
     t = tvals(tidx);
     q1 = - A*h*(Ts - Tf);
     Q = (q1+q2)*dt;
     Ts = (Q/(m*c)) + Ts;
     Tn(tidx) = Ts;
 end
 plot(tvals, Tn);

MATLAB: Basic Vector Operations

Matrices and Arrays

Multiplication (note the dimensions):

 (1:10)   * (21:30).' = scalar  % 1 by 10 times 10 by 1 - inner/dot product
 (1:10).' * (21:30)   = matrix  % 10 by 1 times 1 by 10 - outer product
 (1:10)  .* (21:30)   = vector  % elementwise multiplication

Summation (again note the dimensions)

(1:10)  + 10 or rand(2) + 10 % vector/matrix plus scalar
(1:10)  + (11:20)            % same dim vector addition
rand(2) +  ones(2)           % same dim matrix addition

EDIT

You're retrieving text and doing operations on strings not numbers. To see what I mean try this:

'65' .* '33' 
 65   *  33

To convert strings to numbers a wrapper is:

str2double('65')

or manually for positive numbers:

tmp  = '65' - '0';
nTmp = numel(tmp);
out  = tmp*(10.^(nTmp-1:-1:0)).';

Best Answer

Related Solutions

MATLAB: Graph (some basic)

MATLAB: Basic Vector Operations

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