"index exceeds matrix dimensions" when using str2double
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Heejin Kim
am 27 Jul. 2017
Kommentiert: Heejin Kim
am 27 Jul. 2017
Hi guys.
I am currently attempting to receive data from Arduino and saving them into a Matlab array. I'm not sure why, but I got stuck in an error "index exceeds matrix dimensions" while trying to save str2double value into an array location. I'm wondering if this is because I'm not allowed to save any double values into an array? How should I come across this :( Below I've attached my code.
Thanks in advance.
//////////////////////////////////////
clc
clear s
delete(instrfindall);
%initializing port connection
s=serial('COM7','BaudRate',9600,'DataBits',8);
s.StopBits=1;
fopen(s);
%receiving text info from COM7
n=10;
array=zeros(n,3);
for i=1:n
fprintf(s,'*IDN?');
answer = fscanf(s)
angle=textscan(answer,'%c %s %s %s %c');
array(i,1)=str2double(angle{i,3});
array(i,2)=str2double(angle{i,4});
array(i,3)=str2double(angle{i,5});
end
%converting string info to double and saving them into array
fclose(s);
delete(s)
clear s
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Jan
am 27 Jul. 2017
Bearbeitet: Jan
am 27 Jul. 2017
Text scan replies a cell vector as output. Therefore the first index "angle{*i*, 3}" is misplaced:
for i=1:n
fprintf(s,'*IDN?');
answer = fscanf(s)
angle = textscan(answer,'%c %s %s %s %c');
array(i,1) = str2double(angle{3}); % instead of "angle{i,3}"
The output of textscan will not depend on the loop counter i.
I'm wondering if this is because I'm not allowed to save any double
values into an array?
On one hand it is wise to use phantasy to examine different possible sources of problems. On the other hand, speculations are less useful as the debugger. Type this in the command window:
dbstop if error
or use the corresponding menu of the editor. Then run the code until it stops in the failing line. Now check the details in the command window:
% Failing line: array(i,1)=str2double(angle{i,3});
size(angle)
class(angle)
i
angle{i,3}
str2double(angle{i,3})
which('str2double') % function shadowed by a variable?
Using the debugger is more efficient than asking the forum.
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