Error: The input character is not valid in MATLAB statements or expressions.

Hi, i have an error when i try to run this

t=-2:.1:5;
x=3*exp(0.4*t);
y=2*exp(-0.9*t);
plot(t,x,t,y,':');
legend('x(t)','y(t)')

i'm new to matlab, please help ASAP :( ps : i'm using matlab r2012b

[Nugroho Permata Putra]

my friend use matlab r2013a and it works

[Star Strider]

Please post you actual code, not an image of it.

[Jan]

Please consider the 2nd top most voted thread: http://www.mathworks.com/matlabcentral/answers/29922-why-your-question-is-not-urgent-or-an-emergency and remove the ASAP.

[Nugroho Permata Putra]

t=-2:.1:5;
x=3*exp(0.4*t);
y=2*exp(-0.9*t);
plot(t,x,t,y,':');
legend('x(t)','y(t)')

[Jan]

I've formatted your code. Please read: http://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup. Thanks.

And if you copy and paste this code in the command window, you get the same error?

[Nugroho Permata Putra]

i got the solution, it was t={Character: ASCII Code 2}-2:.1:5; so i need to erase the special char. Sorry my apologies

Answer 1

[Jan]

The error message seems to tell, that the equal character "=" is not valid. How strange. Perhaps it is the space behind the =, which is a backspace charcter '\b' ?!

The code looks okay. How did you insert it to the command window? Simply try to type it again.

What is in the line above? Perhaps a continuation '...' and you've added the ">>" manually? I admit, this is wild guessing.

[Nugroho Permata Putra]

i just copy paste it from the ebook to matlab editor :D

Answer 2

[Kaya Wydler Cunningham]

The input character is not valid in MATLAB statements or expressions.

Error in lv (line 11)
[t,y] = ode45(@lvfun,[0 200],[1 1]); % solve ODE system over

Unsure as to what this means?

[Steven Lord]

One or more of the characters in that expression (or perhaps inside lvfun) should be underlined in red in the Editor. If it is, tell us which one it is; copy and paste it between the single quotes in the following command; and tell us what MATLAB displays when you execute that command.

double('')

My suspicion is that you copied and pasted the code from something (Microsoft Word® for instance) that tries to be "nice" with its formatting. [The most common culprit is the "smart quote".]

[Jan]

@Kaya: Please do not post a new question in the section for answers, but open a new thread. Then post the complete error message. It seems like the most interesting part is missing.

Answer 3

[Ahmed Makhlas]

j'ai une erreur au niveau de la fonction imhist quelq'un qui aide moi

img=imread('lena1.png');

subplot(1,2,1);

imshow(img)

img=rgb2gray(img);

subplot(1,2,2)

imhist(img) %???????????????????????????

Error: File: imhist.m Line: 1 Column: 1

The input character is not valid in MATLAB statements or expressions.

[Steven Lord]

First, I want to check whether you're calling the imhist.m included in Image Processing Toolbox or you're calling an imhist.m that you created or downloaded. What does this command display?

which -all imhist

/MATLAB/toolbox/images/images/imhist.m
/MATLAB/toolbox/images/images/@gpuArray/imhist.m  % Shadowed gpuArray method

If you're using the imhist function from Image Processing Toolbox, I want to check that you haven't accidentally modified it. What does this command display?

dbtype 1:1 imhist.m

1     function [yout,x] = imhist(varargin)

Which release of Image Processing Toolbox are you using?

ver images

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MATLAB Version: 9.9.0.1544872 (R2020b) Update 3
MATLAB License Number: 
Operating System: Linux 4.14.195-0414195-generic #202008260539 SMP Wed Aug 26 11:20:58 UTC 2020 x86_64
Java Version: Java 1.8.0_202-b08 with Oracle Corporation Java HotSpot(TM) 64-Bit Server VM mixed mode
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Image Processing Toolbox                              Version 11.2        (R2020b)