Plotting function was error

when I use fplot I receive an error :

fplot(@(x) ((-v11*x)+v31)/v21)
Error using fplot (line 51)
Not enough input arguments.

Will someone help with this problem?

Davis

Answer 1

[madhan ravi]

Reason for error was variavles were not defined.

syms x
v11=3; %example datas
v31=5;
v21=10;
fplot((-v11*x+v31)/v21)
doc fplot

[YUDE LEE]

I have already defined v11 v31 v21 before

But it still error

Error using fplot (line 51)
Not enough input arguments.

Error in Untitled (line 92)
fplot((-v11*x+v31)/v21)

[madhan ravi]

Might happen that you have made a custom function named fplot() delete it or rename it because it may shadow the inbuilt function:

which fplot -all % what does it show?
which v11 -all
which v21 -all
which v31 -all

[YUDE LEE]

It shows below:

Is it possible my matlab version too old to execute?

which fplot -all 
which v11 -all
which v21 -all
which v31 -all
C:\Program Files\MATLAB\R2014a\toolbox\matlab\specgraph\fplot.m
v11 is a variable.
v21 is a variable.
v31 is a variable.

[madhan ravi]

Is it possible my matlab version too old to execute?

No.

>> which fplot -all
/Applications/MATLAB_R2018b.app/toolbox/matlab/specgraph/fplot.m
fplot is a built-in method                                        % tall method
/Applications/MATLAB_R2018b.app/toolbox/coder/half/@half/fplot.p  % half method -- your missing this file

Contact Mathworks support Team to get that file by clicking the Contact UsContact Us button on the top right corner of this page.

[YUDE LEE]

OK I will try to get that toolbox, thanks for your help.

[madhan ravi]

Anytime :)