Math Forum Discussions

Tiger

Posts: 43
Registered: 6/22/12

Dynamic/variable OutputPort.Dimensions?
Posted: Dec 16, 2012 2:55 PM

Plain Text

Hi folks,

Below is a sample of a text file, called WFtest.txt, that I'm trying to read inside Simulink via a level-2 m-file.
1 0 10 10.8 1
1 1 15 2.55 NaN
1 2 10 54.3 3/4
1 3 15 33.1 1/2/5/6/8

I'm trying to extract one row at a time. The row number is indicated by a variable used as an input in my level2 m-file. My main problem here is reading the last column via textscan(). Mind you, I need to have it eventually converted to 'double' data format because SimEvent's Attributes can only be 'doubles', unfortunately, I hope it can handle others too in the future.

Sometimes, the last column may contain single values, which is fine, sometimes empty, which I handled it by putting a NaN which my code converts it into a NaN('double') if found. Sometimes, it has multiple values, which is the core of my question here. I can, in a seperate mock m-file, extract the different values, in the case of having multiple values in any cell in the last column of the text file, and then convert them into a 'double' format with a dminsion width = 1xn, where 'n' being the number of values in that cell.

However, when I tried embedding the whole thing inside a level-2 m-file, I started having issues with the output port concerning the last column values. I knew I would have such issue, but to be honest I searched around how to tackle it but it didn't work. Below is my level-2 m-file code, and I hope someone can advice me in making the dimensions variable depending on how many values it reads, each time, from that last column.
...
function Level2_WF(block)
setup(block);

function setup(block)
% Register number of ports
block.NumInputPorts = 1; % Indicating which row/line to read from the text file
block.NumOutputPorts = 6;
% Setup port properties to be dynamically inherited
block.SetPreCompInpPortInfoToDynamic;
block.SetPreCompOutPortInfoToDynamic;
% Override input port properties
block.InputPort(1).Dimensions = 1;
block.InputPort(1).DatatypeID = 0; % double
block.InputPort(1).Complexity = 'Real';
block.InputPort(1).SamplingMode = 'Sample';
block.InputPort(1).DirectFeedthrough = true;
% Override output port properties
block.OutputPort(1).Dimensions = 1;
block.OutputPort(1).DatatypeID = 0; % double
block.OutputPort(1).Complexity = 'Real';
block.OutputPort(1).SamplingMode = 'Sample';
block.OutputPort(2).Dimensions = 1;
block.OutputPort(2).DatatypeID = 0; % double
block.OutputPort(2).Complexity = 'Real';
block.OutputPort(2).SamplingMode = 'Sample';
block.OutputPort(3).Dimensions = 1;
block.OutputPort(3).DatatypeID = 0; % double
block.OutputPort(3).Complexity = 'Real';
block.OutputPort(3).SamplingMode = 'Sample';
block.OutputPort(4).Dimensions = 1;
block.OutputPort(4).DatatypeID = 0; % double
block.OutputPort(4).Complexity = 'Real';
block.OutputPort(4).SamplingMode = 'Sample';
block.OutputPort(5).Dimensions = -1; % How can I make this variable?
block.OutputPort(5).DatatypeID = 0; % 0=double, -1=inherited
block.OutputPort(5).Complexity = 'Real';
block.OutputPort(5).SamplingMode = 'Sample';
block.OutputPort(6).Dimensions = 1;
block.OutputPort(6).DatatypeID = 0; % double
block.OutputPort(6).Complexity = 'Real';
block.OutputPort(6).SamplingMode = 'Sample';
block.SampleTimes = [-1 0];
block.SimStateCompliance = 'DefaultSimState';
% Outputs: Called to generate block outputs in simulation step
block.RegBlockMethod('Outputs', @Outputs);

function Outputs(block)
fid = fopen('WFtest.txt');
% The following if-statement ensures the row number is a positive integer.
if isempty(block.InputPort(1).Data) == 1 || block.InputPort(1).Data <= 0
block.InputPort(1).Data = 1;
end
a = textscan(fid, '%f %f %f %f %s', 1, 'delimiter', '', 'headerlines', block.InputPort(1).Data-1);
block.OutputPort(1).Data = a{1}; % J_ID
block.OutputPort(2).Data = a{2}; % T_ID
block.OutputPort(3).Data = a{3}; % Cores
block.OutputPort(4).Data = a{4}; % T_ET
Deps = a{5}; % Raw values with '/' inbetween
% The following if-statement checks if a{5} is NaN or not.
if strcmp(Deps, 'NaN') == 1
block.OutputPort(5).Data = NaN('double'); % 1x1 double
else
block.OutputPort(5).Data = sscanf(cell2mat(Deps), '%d/')'; % Deps. (1xn double), Output(5)Dimensions to be dynamic, how?
end
block.OutputPort(6).Data = a{4} * 1.2; % Deadline
fclose(fid)
...

It worked well for the first 2 rows, but it gave me the inevitable error (Invalid assignment in 'Level2_WF_test/Level-2 M-file S-Function (Reading from WF.txt)': attempt to assign a vector of width 2 to a vector of width 1.) for the third row, and it pointed at the 'sscanf' line in the code above.

Any advice?
_________________
Many thanks.