How can i solve the " Subscripted assignment dimension mismatch. Error in fi2 (line 12) u(:,1)= -sin(pi.*x) " ?

here is the code :

a = input('Insert the value of a: ');
CFL = input('Insert the value of CFL: ');
dx = input('Insert the value of dx: ');
dt = (CFL * dx)/ abs(a);
lambda = (dt/dx)
tf = input('Insert final time : ');
N = input('Insert the value of N: ');
x = linspace(-1,1,N);
%choose test case:
tc= input('choose test case number : ');
if tc == 1 
    u(:,1)= -sin(pi.*x)

Answer 1

[ME]

I have just run this code in R2016a and it did not produce an error when I chose a random set of input parameters. Was there a specific set of input parameters that produce this issue for you?

[guetty abboud]

• a = 1
• CFL = 0.8
• tf = 4
• dx = 4/50
• N = 40

( the error is the same for me no matter what tc i choose)

[guetty abboud]

it was a file error. you were right, once i copied the code to a new script it worked. thanks

[ME]

Just tried again after inputting the parameters you suggested with tc=1 and did not get the error.

Apologies for asking a stupid question but in your script I assume you have the 'end' that is missing from the code in your problem description?

Also, is there supposed to be more code after the below lines? If not then your script produces no u array unless tc=1.

if tc == 1 
    u(:,1)= -sin(pi.*x)

[guetty abboud]

yes of course there are other conditions for tc. and no i didn't forget the end in the code. thanks for noticing though. please may you refer to my other question which is a new error I am confronting ?