Not Enough Input Arguments

Hi, I'm very new to MATLAB and I am having some trouble. Lots of people have had the same problem but nobody seems to be able to explain or solve it in plain English. Could somebody please explain what this error is and how to fix it?

I have a simple function:

function [r]=Mec134function(w,theta_deg)
    t2=10000;
    theta_rad=(theta_deg./180).*pi;
    t1=55090./(10*sin(theta_rad));
    rx=(t1.*cos(theta_rad))-t2;
    ry=w-(t1.*sin(theta_rad));
    r=((rx).^2+(ry).^2).^0.5;
end

It seems to give this error for line 3 but I'm not sure why.

Thanks.

[Jonathan Epperl]

You call a function with not enough input arguments, as an example

sin()

will give you that error, because sin needs an argument -- what number do you want to compute the sine of?

Maybe you should start by working through the "Getting Started" in the Matlab Help, won't take you long but make a lot of things clear.

[Vijayan G]

[rows,M]=size(r); if (rows > M) M=rows; r=r'; end;

i am getting error in this like

Not enough input arguments

[xiao8572]

Maybe this is a function, such as : Function s = sum(a , b) , you should input some arguments, a and b. Hope my answer could help you .

[Chaitanya Bade]

Hi, I am having the same issue with the below code. would you be able to help me out with this please. Thanks in advance. [fitresult, gof] = fit(n, rn)

[Jan]

@Chaitanya: The error message is clear: The function fit() requires more than 2 inputs. See https://www.mathworks.com/help/curvefit/fit.html.

[Shrooq Alanazi]

hi, I have a problem in Matlab code send me this message in runtime

 Not enough input arguments.

Error in PCA (line 2) cov_img_train = m_img_train'*m_img_train;

how to solve

[Walter Roberson]

You need to pass a vector or 2D array as an argument to your PCA function. Or perhaps your m_img_train is somehow defined as a function.

[krishnama raju]

sir in this code executing in matlab showing error in line 38.https://codeocean.com/capsule/7635653/tree/v1

[Walter Roberson]

Line 38 of which function?

Answer 1

[Akiva Gordon]

Your function defines 2 input arguments (w and theta_deg). When you run Mec134function, you must specify exactly two inputs, otherwise you will get the error "Not enough input arguments".

For example, if you run the Mec134function in the command window without specifying any arguments:

>> Mec134function

You get this error:

Not enough input arguments.
Error in Mec134function (line 3)
theta_rad=(theta_deg./180).*pi;

If you run the Mec134function and specify two input arguments, "w" and "theta_deg" (assuming "w" and "theta_deg" are defined), you do not get the error message:

>> Mec134function(w,theta_deg)

If you have the file "Mec134function.m" open in the Editor and you try to run the function by pressing the "Run" button or F5, MATLAB runs the Mec134function without any input arguments, and you get the error "Not enough input arguments". The "Run" button dropdown menu then opens prompting you to enter values for the missing input arguments.

Add the desired values and press enter. The values you enter are set as the default inputs when you click the "Run" button or F5 in the future.

To change the values, press the down arrow below the "Run" button and enter new values.

[Nyasha Suliali]

Thank you Akiva, entering the complete function (with variables as in its definition) worked for me!

[Guiyeoul Lim]

Thanks man! that worked!

[sayima mukhtar]

But after doing this it shows

Unrecognized function or variable 'X'.

[Walter Roberson]

Are you sure? I do not see any x or X variable in any code here until you scroll way down to

https://www.mathworks.com/matlabcentral/answers/53100-not-enough-input-arguments#answer_248618

[Evan Curatolo]

Oh man. Bless your soul. Thank you for this comment.

Answer 2

[TheLimpNinja]

sorry the function is

function [r]=Mec134function(w,theta_deg)

t2=10000;

theta_rad=(theta_deg./180).*pi;

t1=55090./(10*sin(theta_rad));

rx=(t1.*cos(theta_rad))-t2;

ry=w-(t1.*sin(theta_rad));

r=((rx).^2+(ry).^2).^0.5;

end

if that's clearer :-)

[Jonathan Epperl]

This function needs 2 input arguments, w and theta_deg. If you type into the command window

Mec134function(2*pi, 120)

you should not be getting an error. If you do, please post your whole command and the whole error message.

[David Barry]

Jonathan is correct, please ignore the other answer below.

As a complete aside, MATLAB has commands deg2rad and rad2deg.

[Steven Lord]

Prior to release R2015b the deg2rad and rad2deg functions were part of Mapping Toolbox. In that release they moved into MATLAB.

As another solution that avoids converting between degrees and radians, MATLAB also has functions sind and cosd for computing the sine and cosine of angles in degrees and those have been part of MATLAB for quite some time. [I don't remember exactly when they were introduced.]

Answer 3

[TheLimpNinja]

Thanks :-)

will have a look at the "getting started"

I have a simple function:

function [r]=Mec134function(w,theta_deg)
t2=10000;
theta_rad=(theta_deg./180).*pi;
t1=55090./(10*sin(theta_rad));
rx=(t1.*cos(theta_rad))-t2;
ry=w-(t1.*sin(theta_rad));
r=((rx).^2+(ry).^2).^0.5;
end

that seems to give this error for line 2 but I'm not sure why.

[Jan]

@TheLimpNinja: Please add all details, which describe the problem in the questions - you can edit it. The answers section is reserved for answers.

[Waldemiro Kubucama]

Hello, first press button "Run" in Matlab and after only you press the button "ENTER" i your computer. I think your problem will be solved.

Answer 4

[Brian Batson]

I too am very new to Matlab, and tried to run the code above in .m (JP Donlon on Nov. 7th). However, I keep getting an error stating "Not enough input arguments." I'm not sure what this means, because I have attempted to run other code by professors which works on other computers. Is it something with my preference settings?

Also, when I run the Code Analyzer, there are no issues...not sure what is going on.

[Walter Roberson]

How are you initiating the running of the code?

[Image Analyst]

When you called Mec134function(), did you pass in two arguments, or did you even pass in any arguments at all? You didn't just write that code into Mec134function.m and click the green run button did you? Because it needs two arguments. Did you pass it two arguments? That's what it means when it says "Not enough input arguments" - that you didn't pass in enough input arguments.

[Prerna Singh]

Hi,

Could you please explain what do you mean by passing the arguments?

Thanks

prerna

[Walter Roberson]

https://www.mathworks.com/matlabcentral/answers/53100-not-enough-input-arguments#comment_109973

Answer 5

[Annie micheal]

How to rectify this error

Error using DetectFace (line 68)
Not enough input arguments.

the code is given below

I=imread('lena.jpg');
minFace = 20; % minimal size of the face that you are searching for 
maxFace = 4000; % maximal size of the face that you are searching for 
overlappingThreshold = 0.5; % overlapping threshold for grouping nearby detections
numThreads = 24; % number of cpu threads for parallel computing

if nargin > 2 && ~isempty(options)
    if isfield(options, 'minFace') && ~isempty(options.minFace)
        minFace = options.minFace;
    end
    if isfield(options, 'maxFace') && ~isempty(options.maxFace)
        maxFace = options.maxFace;
    end
    if isfield(options, 'overlappingThreshold') && ~isempty(options.overlappingThreshold)
        overlappingThreshold = options.overlappingThreshold;
    end
    if isfield(options, 'numThreads') && ~isempty(options.numThreads)
        numThreads = options.numThreads;
    end
end

%%test detector

if ~ismatrix(I)
    I = rgb2gray(I);
end

candi_rects = NPDScan(model, I, minFace, maxFace, numThreads);

%%post processing
if isempty(candi_rects)
    rects = [];
    return;
end

[Walter Roberson]

Please post the complete error message, everything in red.

The use of nargin, and the return near the end of the code, suggest strongly that you have posted part of the code for a function. We need to see the entire function, and we need to see what arguments you passed to the function.

NPDScan is not part of MATLAB. Are you getting it from https://github.com/biotrump/NPD/blob/master/NPDFaceDetector_Train/src/NPDScan.cpp ?

[Annie micheal]

yeah i got it from NPDFaceDetector...

the entire code is

I=imread('lena.jpg');
minFace = 20; % minimal size of the face that you are searching for 
maxFace = 4000; % maximal size of the face that you are searching for 
overlappingThreshold = 0.5; % overlapping threshold for grouping nearby detections
numThreads = 24; % number of cpu threads for parallel computing

if nargin > 2 && ~isempty(options)
    if isfield(options, 'minFace') && ~isempty(options.minFace)
        minFace = options.minFace;
    end
    if isfield(options, 'maxFace') && ~isempty(options.maxFace)
        maxFace = options.maxFace;
    end
    if isfield(options, 'overlappingThreshold') && ~isempty(options.overlappingThreshold)
        overlappingThreshold = options.overlappingThreshold;
    end
    if isfield(options, 'numThreads') && ~isempty(options.numThreads)
        numThreads = options.numThreads;
    end
end

%%test detector

if ~ismatrix(I)
    I = rgb2gray(I);
end

candi_rects = NPDScan(model, I, minFace, maxFace, numThreads);

%%post processing
if isempty(candi_rects)
    rects = [];
    return;
end

numCandidates = length(candi_rects);
predicate = eye(numCandidates); % i and j belong to the same group if predicate(i,j) = 1

% mark nearby detections
for i = 1 : numCandidates
    for j = i + 1 : numCandidates
        h = min(candi_rects(i).row + candi_rects(i).size, candi_rects(j).row + candi_rects(j).size) - max(candi_rects(i).row, candi_rects(j).row);
        w = min(candi_rects(i).col + candi_rects(i).size, candi_rects(j).col + candi_rects(j).size) - max(candi_rects(i).col, candi_rects(j).col);
        s = max(h,0) * max(w,0);

          if s / (candi_rects(i).size^2 + candi_rects(j).size^2 - s) >= overlappingThreshold
              predicate(i,j) = 1;
              predicate(j,i) = 1;
          end
      end
  end

% merge nearby detections
[label, numCandidates] = Partition(predicate);

rects = struct('row', zeros(numCandidates,1), 'col', zeros(numCandidates,1), ...
    'size', zeros(numCandidates,1), 'score', zeros(numCandidates,1), ...
    'neighbors', zeros(numCandidates,1));

for i = 1 : numCandidates
    index = find(label == i);
    weight = Logistic([candi_rects(index).score]');
    rects(i).score = sum( weight );
    rects(i).neighbors = length(index);

      if sum(weight) == 0
          weight = ones(length(weight), 1) / length(weight);
      else
          weight = weight / sum(weight);
      end

      rects(i).size = floor([candi_rects(index).size] * weight);
      rects(i).col = floor(([candi_rects(index).col] + [candi_rects(index).size]/2) * weight - rects(i).size/2);
      rects(i).row = floor(([candi_rects(index).row] + [candi_rects(index).size]/2) * weight - rects(i).size/2);
  end

clear candi_rects;

% find embeded rectangles
predicate = false(numCandidates); % rect j contains rect i if predicate(i,j) = 1

for i = 1 : numCandidates
    for j = i + 1 : numCandidates
        h = min(rects(i).row + rects(i).size, rects(j).row + rects(j).size) - max(rects(i).row, rects(j).row);
        w = min(rects(i).col + rects(i).size, rects(j).col + rects(j).size) - max(rects(i).col, rects(j).col);
        s = max(h,0) * max(w,0);

          if s / rects(i).size^2 >= overlappingThreshold || s / rects(j).size^2 >= overlappingThreshold
              predicate(i,j) = true;
              predicate(j,i) = true;
          end
      end
  end

flag = true(numCandidates,1);

% merge embeded rectangles
for i = 1 : numCandidates
    index = find(predicate(:,i));

      if isempty(index)
          continue;
      end

      s = max([rects(index).score]);
      if s > rects(i).score
          flag(i) = false;
      end
  end

rects = rects(flag);

% check borders
[height, width, ~] = size(I);
numFaces = length(rects);

for i = 1 : numFaces
    if rects(i).row < 1
        rects(i).row = 1;
    end

      if rects(i).col < 1
          rects(i).col = 1;
      end

      rects(i).height = rects(i).size;
      rects(i).width = rects(i).size;

      if rects(i).row + rects(i).height - 1 > height
          rects(i).height = height - rects(i).row + 1;
      end

      if rects(i).col + rects(i).width - 1 > width
          rects(i).width = width - rects(i).col + 1;
      end    
  end
  end

function Y = Logistic(X)
    Y = log(1 + exp(X));
    Y(isinf(Y)) = X(isinf(Y));
end

[Walter Roberson]

Why did you use nargin and return when you wrote this script ? nargin is defined as being 0 within scripts and return can lead to odd behavior when used within a script .

When I search around, it looks to me as if this code is ripped off from https://github.com/biotrump/NPD/blob/master/NPDFaceDetector/DetectFace.m which is a function not a script . An example of calling that function is given in the comments there:

     I = imread('lena.jpg');
     load('model.mat');
     rects = DetectFace(npdModel, I);

You cannot just remove the function line from a function and assign to one variable and expect it to work.

Answer 6

[REEMA MOHANTY]

clc; clear; close all;
xo=0.4;
A=[];
b=[];
Aeq=[];
beq=[];
 Q=100;
 R=1;
N = 50;
U0= zeros(100,1);
% Umin= -1*ones(100,1);
% Umax=1*ones(100,1);
% U = fmincon(@cost1,U0,A,b,Aeq,beq,Umin,Umax,[],[],N);
x=xo; h = 0.1;
xo=[-0.5,0.5];
options = optimoptions(@fmincon,'Algorithm','sqp');
U = fmincon(@cost1,U0,[],[],[],[],[],[],@confuneq,options);
for k =1:N
    S1= F(x(k),U(k));
    S2=F(x(k)+0.5*h*S1,U(k));
    S3=F(x(k)+0.5*h*S2,U(k));
    S4=F(x(k)+h*S3,U(k));
    x(k+1) = x(k) + (1/6)* (S1+ 2*S2+ 2*S3 + S4)*h;
    k = k + 1 ;   
end

% plot(x);
 plot(U);
 grid on
 figure(); plot(x)
grid on

I new to matlab.Can anyone help me to fix the iisue here.

Its showing not enough input arguments.

Answer 7

[vani shree]

Hello sir,I am newer to matlab. I am getting error in this code like "preprocessing requries more input arugument to run". can you please to run this program. my project topic is recognition and matching fake logos using filters.

   function img=preprocessing(I)
  [x y o]=size(I);
  if o==3
     I=rgb2gray(I);
  end
  I=im2double(I);
  %%MEDIAN FILTER
  med=medfilt2(I);
  figure,imshow(med)
  title('MEDIAN FILTERED IMAGE')
  [psnr_med,mse_med]=psnr(I,med)

%%AVERAGE FILTER
out7= imfilter(I, fspecial('average'));
figure,imshow(out7)
title('MEAN FILTERED IMAGE')
[psnr_avg,mse_avg]=psnr(I,out7)

%%GAUSSIAN FILTER
gau=imfilter(I,fspecial('gaussian'));
figure,imshow(gau)
title('GAUSSIAN FILTER IMAGE')
[psnr_gau,mse_avg]=psnr(I,gau)

%%WEINER FILTER
psf=fspecial('gaussian',7,10);
image1=imfilter(I,psf,'conv','circular');
var1=(1/256)^2/12;
var2=var(I(:));
wei=deconvwnr(image1,psf,(var1/var2));
figure,imshow(wei);title('WEINER FILTERED IMAGE');
[psnr_wei,mse_wei]=psnr(I,wei)

psnr_all=[psnr_med,psnr_avg,psnr_gau,psnr_wei];
psnr_max=max(psnr_all);
val=find(psnr_all==psnr_max);
if val==1
    img=med;
    disp('median have high psnr');
elseif val==2
    img=out7;
    disp('mean have high psnr');
elseif val==3
    img=gau;
    disp('gaussian have high psnr');
else
    img=wei;
    disp('weiner have high psnr');

end

[Walter Roberson]

You cannot (typically) run functions just by clicking on the Run button. You have to go down to the command line and give the function name and indicate what parameters you are passing to it.

For example, at the command line you might do

MyImage = imread('cameraman.tif');
MyNewImage = preprocessing(MyImage);

This creates an image in the first line, and passes it to the preprocessing function in the second line, and assigns the result of preprocessing to the variable MyNewImage

[vani shree]

thank you very much sir. and i have some other doubts regarding my project.my project title is recognition and detection of lake logos by context. i done 60% of coding like preprocessing and SIFT process but i dont know how to compare fake logo and original logo and the output should display which is fake logo. can u please help me to compare these two images.

[Steven Lord]

vani shree, you should ask this as a separate question since it's not related to the "not enough input arguments" original question. Show what you've written and ask a specific question about where you're having difficulty and you may receive some guidance.

Answer 8

[Ganesh Petkar]

I am getting error for below function as "Not enough input arguments. "

delayed_signal = mtapped_delay_fcn(input);

[Walter Roberson]

input is a MATLAB function call. See https://www.mathworks.com/help/matlab/ref/input.html

Answer 9

[Wendell]

Hi I'm trying to run Dr. John Stockie's matlab code but I am getting a "Not enough input argument" error. I'm not very well verse with Matlab, so I would appreciate any help...Thank you. I am pasting the code:

function C = ermak( x, y, z, H, Q, U, Wset, Wdep )
% ERMAK: Compute contaminant concentration (kg/m^3) using the
%   Gaussian plume model, modified for a deposition and settling
%   velocity.  This code handles a single source (located at the
%   origin) and multiple receptors.
%
% Input parameters:
%
%     x - receptor locations: distance along the wind direction, with
%         the source at x=0 (m) 
%     y - receptor locations: cross-wind direction (m)
%     z - receptor locations: vertical height (m)
%     H - source height (m)
%     Q - contaminant emission rate (kg/s)
%     U - wind velocity (m/s)
%     Wset - gravitational settling velocity (m/s)
%     Wdep - deposition velocity (m/s)
%
% Output:
%
%     C - contaminant concentration (kg/m^3)
%
% References: Ermak (1977), Winges (1990/1992).

% First, define the cut-off velocity, below which concentration = 0.
Umin      = 0.0;

% Determine the sigma coefficients based on stability class C --
% slightly unstable (3-5 m/s). 
ay = 0.34;  by = 0.82;  az = 0.275; bz = 0.82;  
sigmay = ay*abs(x).^by .* (x > 0);
sigmaz = az*abs(x).^bz .* (x > 0);

% Calculate the eddy diffusivity (m^2/s).
Kz = 0.5*az*bz*U*abs(x).^(bz-1) .* (x > 0);  % K = 0.5*U*d(sigma^2)/dx

% Calculate the contaminant concentration (kg/m^3) using Ermak's formula.
if U < Umin,
  C = 0 * z;
else
  Wo = Wdep - 0.5*Wset;
  C  = Q ./ (2*pi*U*sigmay.*sigmaz) .* exp( -0.5*y.^2./sigmay.^2 ) .* ...
       exp( -0.5*Wset*(z-H)./Kz - Wset^2*sigmaz.^2/8./Kz.^2 ) .* ...
       ( exp( -0.5*(z-H).^2./sigmaz.^2 ) + ...
   exp( -0.5*(z+H).^2./sigmaz.^2 ) - sqrt(2*pi)*Wo*sigmaz./Kz .* ...
   exp( Wo*(z+H)./Kz + 0.5*Wo^2*sigmaz.^2./Kz.^2 ) .* ...
   erfc( Wo*sigmaz/sqrt(2)./Kz + (z+H)./sqrt(2)./sigmaz ) );
  ii = find(isnan(C) | isinf(C));
  C(ii) = 0;   % Set all NaN and inf values to zero.
end

and the error message refers to "sigmay" in line 31

[Walter Roberson]

Please read the previous Answers here.

Answer 10

[aarthy reddy R]

function test(num1, num2,small,s)
load (small, num1, num2)
s = sum(num1, num2)
end

this the code for this i'm getting these errors

Not enough input arguments.
Error in test (line 3)
load (small, num1, num2)

[Walter Roberson]

You are trying to run the function without providing any input arguments.

What is the expected datatype of the variable named small? At the moment I cannot think of any Mathworks supplied class that has a method named load() that takes 3 arguments.

[aarthy reddy R]

load(filename, var1, var2)

so it is having 3 arguments

[Walter Roberson]

Okay, well you are trying to run test without passing in at least 3 input arguments. For example you might be trying to just press the green Run button, instead of going down to the command line and issuing a command in the command window.

[Walter Roberson]

Note: if you pass in the name of a variable as the fourth parameter, then the function you posted will not set that variable to the result of the sum. If you want to return a value in MATLAB you need to code it on the left side of an "=" in the function line. For example,

function s = test(num1, num2, small)
    load (small, num1, num2)
    s = sum(num1, num2)
end

This is unlikely to work the way you want it. In order for the load() to work there, small and num1 and num2 would each have to be a character vector or else a scalar string variable, and num1 and num2 would have to be in the same form as valid MATLAB variable names. Those names would have to be found inside the .mat file named by the small variable.

With the form of load() you have used, MATLAB would normally "poof" the variable names into existence. However, when you use end matching a function statement, you make a promise to MATLAB that you will not poof variables into existence, and MATLAB is permitted to give an error or to ignore the magically created variables. Therefore after the load, num1 and num2 are probably going to continue to be the character vectors or string objects, and you would attempt to call sum() passing those in. sum() would give an error if the first parameter, num1 is a string object, but would be okay with num1 being a character vector. There are a limited number of character vectors or scalar string objects that are valid for the second parameter of sum(), namely 'all', 'double', 'native', 'default', 'includenan', or 'omitnan' . It would be surprising if you happened to name your variables any of those...

Answer 11

[Chapat]

Hello. Am new in Matlab and I want to do my assignment with this function refraction_2layers and Matlab is saying error using refraction_2layers (line 18 and 25) Here is the whole program

function refraction_2layers(v1, v2, z, FIRST_ARRIVALS_ONLY);
% refraction_2layers(v1, v2, z);
%
% Creates travel time plots for a two-layers system with layer velocities 
% v1 and v2 and layer 1 thickness of z 
% The FIRST_ARRIVALS_ONLY FLAG may be set to 1 to plot only the first arrivals. By
% default, all arrivals are plotted.
if nargin < 4 FIRST_ARRIVALS_ONLY = 0; end
%% X-positions for geophones (m, relative to source)
x = [0:5:300];
%% Direct wave %% Travels along ground surface (at velocity v1)
t1 = x./v1;
%% Head wave
%% Refracts along z1-z2 boundary
%% Travel time depends on velocities of both layers 
%% and thickness of layer 1 only (thickness of layer 2 irrelevant)
t2 = (2*z*sqrt(v2^2-v1^2)/(v1*v2))+x./v2; %% Note slope should be 1/v2!
xcrit = 2*z*v1/(sqrt(v2^2-v1^2));
if isreal(xcrit)
    a = min(find(x>xcrit));
end
crossover = ((2*z*sqrt(v2^2-v1^2))/(v1*v2))/(1/v1-1/v2);
b = max(find(x<= crossover));
if FIRST_ARRIVALS_ONLY
    plot(x(1:b),t1(1:b)*1000, '.--')
    hold on
    if isreal(t2)
        plot(x(b:end), t2(b:end)*1000, 'r.--')
    end
else
    plot(x,t1*1000, '.--')
    hold on
    if isreal(t2)
        plot(x(a:end), t2(a:end)*1000, 'r.--')
    end
end

xlabel('GEOPHONE OFFSET (m)')
    ylabel('TIME (ms)')
    grid on 
    legend('DIRECT WAVE', 'HEAD WAVE')
    title(['z1 = ', num2str(z), ' m; v1 = ', num2str(v1), ' m/s; v2 = ', num2str(v2), ' m/s'])
    axis ([0 300 0 300])
    hold off

[Walter Roberson]

Chapat:

I formatted your code for you to make it readable to other people, but I suspect that I did not exactly preserve the line boundaries, so we do not know which lines are giving you the problem. Please mark them by using comments. Please also give the exact error messages.

Also please check the position of the end statements. It looked to me as if you might have had two extra end statements.

Answer 12

[Josilyn Dostal]

I am really struggling to figure out this "not enough input arguments" error in my code. Any help would be greatly appreciated! This is for a batch distillation problem, and the error is referring to the temp function near the bottom. The code and error are below:

P = 912; % mmHg or 1.2 atm
L0 = 100; % Moles liquid in the still initially
A = [6.90565 6.95464]; B=[1211.033 1344.8]; C=[220.79 219.482]; % Antoine Constants
% x0 = [0.60 0.40]; % Initial liquid concentration xb = 60% xt = 40%
% xf = [0.20 0.80]; % Final liquid concentration xb = 20% xt = 80%
xtspan = linspace(0.40,0.80,100);
[xt, L] = ode45(@Moles, xtspan, L0);
L = L(end);
fprintf('The amount of liquid remaining in the still when liquid mole fraction of toluene reaches 0.80 is %f moles', L);

    % Vapor liquid equilibrium ratio, K
    function Kt = EquilibriumRatio(Psatt)   
        Kt = Psatt/P;
    end    
        % Toluene vapor pressure
        function Psatt = VaporPressuret(T,A,B,C)
            Psatt = 10^(A(2)-B(2)/(T+C(2)));
        end
            % Benzene vapor pressure
            function Psatb = VaporPressureb(T,A,B,C)
                Psatb = 10^(A(1)-B(1)/(T+C(1)));
            end
                % ODE
                function dLdx = Moles(xt,L)
                    T0 = 95.585;
                    %options = odeset('RelTol',1e-6,'AbsTol',1e-8);
                    %options = optimset('PlotFcns',{@optimplotx,@optimplotfval});
                    %options = optimset('Display','iter'); % show iterations
                    options = optimset('Display','off','TolX',1e-6); % Options
                    T = fzero(@temp, T0, options);
                    Psatt = VaporPressuret(T);
                    Kt = EquilibriumRatio(Psatt);
                    dLdx = L/(xt*(Kt-1));
                end
function Tempfun = temp(T,xt,P,A,B,C)
    Psatt = VaporPressuret(T,A,B,C);
    Psatb = VaporPressureb(T,A,B,C);
    Tempfun = Psatt*xt + Psatb*(1-xt) - P;
end

>> project2
Error using fzero (line 306)
FZERO cannot continue because user-supplied function_handle ==> temp failed with the error below.

 Not enough input arguments.

Error in project2>Moles (line 30)
                    T = fzero(@temp, T0, options);

Error in odearguments (line 90)
f0 = feval(ode,t0,y0,args{:});   % ODE15I sets args{1} to yp0.

Error in ode45 (line 115)
  odearguments(FcnHandlesUsed, solver_name, ode, tspan, y0, options, varargin);

Error in project2 (line 7)
[xt, L] = ode45(@Moles, xtspan, L0);

[Walter Roberson]

you are expecting that when your script calls ode45 and that ode45 calls Moles and that Moles calls fzero and fzero calls temp, that temp will somehow look all the way back up the chain to find values for xt P A B C to use in temp.

That never happens. There are no situations in MATLAB in which a missing named parameter has its value found by chasing up the chain of calls to find a variable with the same name as the variable.

And if there were such an resolution operation, what would you do if it turned out that ode45 had variables named A and B and so those values ended up being used instead of following all the way back to the script? Such an operation would require that the child function (temp) know the name of all of the calling functions' variables so as to avoid an accidental name clash. This would be poor programming design.

This is why in all major programming languages, resolution of variables is either positional or lexical (controlled by where the variables declared).

I recommend https://www.mathworks.com/help/matlab/math/parameterizing-functions.html

[Josilyn Dostal]

Thank you! i will try that.

[Josilyn Dostal]

Sorry to ask again, but i did what you said and am now getting a different error. The "not enough input arguments" error is gone, so that's great, thank you! Now the error has a problem with the "+" in my vapor pressure function, which makes no sense to me. Do you have any idea what this means? The code and error are below.

P = 912; % mmHg or 1.2 atm
L0 = 100; % Moles liquid in the still initially
% x0 = [0.60 0.40]; % Initial liquid concentration xb = 60% xt = 40%
% xf = [0.20 0.80]; % Final liquid concentration xb = 20% xt = 80%
xtspan = linspace(0.40,0.80,100);
[xt, L] = ode45(@Moles, xtspan, L0);
L = L(end);
fprintf('The amount of liquid remaining in the still when liquid mole fraction of toluene reaches 0.80 is %f moles', L);

    % Vapor liquid equilibrium ratio, K
    function Kt = EquilibriumRatio(Psatt)   
        Kt = Psatt/P;
    end    
        % Toluene vapor pressure
        function Psatt = VaporPressuret(T)
           At = 6.95464; 
           Bt = 1344.8; 
           Ct = 219.482; % Antoine Constants
           Psatt = 10^(At-(Bt/(T+Ct)));
        end
            % Benzene vapor pressure
            function Psatb = VaporPressureb(T)
                Ab = 6.90565;
                Bb = 1211.033;
                Cb = 220.79;    % Antoine Constants
                Psatb = 10^(Ab-(Bb/(T+Cb)));
            end
                % ODE
                function dLdx = Moles(xt,L)
                    
                    % fzero
                    function T = findzero(~)
                        T0 = 95.585;
                        T = fzero(@temp, T0);
                        
                        % Temperature
                        function Tempfun = temp(T,xt,P)
                                Psatt = VaporPressuret(T);
                                Psatb = VaporPressureb(T);
                                Tempfun = Psatt*xt + Psatb*(1-xt) - P;
                        end 
                    end
                
                    T = @findzero;
                    Psatt = VaporPressuret(T);
                    Kt = EquilibriumRatio(Psatt);
                    dLdx = L/(xt*(Kt-1));
                end
                

Operator '+' is not supported for operands of type 'function_handle'.

Error in project5>VaporPressuret (line 19)
           Psatt = 10^(At-(Bt/(T+Ct)));

Error in project5>Moles (line 45)
                    Psatt = VaporPressuret(T);

Error in odearguments (line 90)
f0 = feval(ode,t0,y0,args{:});   % ODE15I sets args{1} to yp0.

Error in ode45 (line 115)
  odearguments(FcnHandlesUsed, solver_name, ode, tspan, y0, options, varargin);

Error in project5 (line 6)
[xt, L] = ode45(@Moles, xtspan, L0);                

[Walter Roberson]

P = 912; % mmHg or 1.2 atm
L0 = 100; % Moles liquid in the still initially
A = [6.90565 6.95464]; B=[1211.033 1344.8]; C=[220.79 219.482]; % Antoine Constants
% x0 = [0.60 0.40]; % Initial liquid concentration xb = 60% xt = 40%
% xf = [0.20 0.80]; % Final liquid concentration xb = 20% xt = 80%
xtspan = linspace(0.40,0.80,100);
[xt, L] = ode45(@(xt,L) Moles(xt,L,P,A,B,C), xtspan, L0);
L = L(end);
fprintf('The amount of liquid remaining in the still when liquid mole fraction of toluene reaches 0.80 is %f moles', L);

% ODE
function dLdx = Moles(xt, L, P, A, B, C)
    T0 = 95.585;
    %options = odeset('RelTol',1e-6,'AbsTol',1e-8);
    %options = optimset('PlotFcns',{@optimplotx,@optimplotfval});
    %options = optimset('Display','iter'); % show iterations
    options = optimset('Display','off','TolX',1e-6); % Options
    T = fzero(@(T)temp(T,xt,P,A,B,C), T0, options);
    Psatt = VaporPressuret(T, A, B, C);
    Kt = EquilibriumRatio(Psatt, P);
    dLdx = L/(xt*(Kt-1));
end

function Tempfun = temp(T, xt, P, A, B, C)
  Psatt = VaporPressuret(T, A, B, C);
  Psatb = VaporPressureb(T, A, B, C);
  Tempfun = Psatt*xt + Psatb*(1-xt) - P;
end

% Toluene vapor pressure
function Psatt = VaporPressuret(T, A, B, C)
  Psatt = 10^(A(2)-B(2)/(T+C(2)));
end

% Vapor liquid equilibrium ratio, K
function Kt = EquilibriumRatio(Psatt, P)   
  Kt = Psatt/P;
end

% Benzene vapor pressure
function Psatb = VaporPressureb(T, A, B, C)
  Psatb = 10^(A(1)-B(1)/(T+C(1)));
end

[Josilyn Dostal]

You are my savior. Youre so nice.

Answer 13

[Maria hassan]

Hi,

I am getting error 'Not enough input arguments.' I am trying online trail oversion. When I click run icon, it does not allow me to enter the value for the input as there is no option for entering the values. Any advice here please?

Best

Sarah

Answer 14

[Gurwinder pal singh Bhinder]

hi

I am new to matlab. i am getting error message "extract_features" requires more input arguments to run.

anderror in command window :

>> Extract_Features

Not enough input arguments.

Error in Extract_Features (line 2)

img1 = imread(filename);

code is written below:

function Extract_Features(filename,flag)
img1 = imread(filename);
if ndims(img1) == 3; img1 = rgb2gray(img1); end  % Color Images
disp(['Extracting features from ' filename ' ...']);
fir=ext_finger(img1,0);
fir=fir(fir(:,3)<5,:);
if flag ==1
    figure;
    imshow(img1);
    hold on
    fir1=find(fir(:,3)==1);
    fir3=find(fir(:,3)==3);   
    plot(fir(fir1,1),fir(fir1,2),'r+');
    plot(fir(fir3,1),fir(fir3,2),'bo');
end
filename2=filename; filename2(end-1)='x'; filename2(end)='t';
save(filename2,'fir','-ascii');
end

[Walter Roberson]

When you run your code, which image file do you expect it to extract the features of?

[Gurwinder pal singh Bhinder]

firstly, i run this code which ask for image and i select image and it extract features. there are four images. i extract features of these four images by running this code four times ( i dont know this is right thing to do), it gives four .txt files.

after that i run the code i mentioned in previously , but that code gives error as i mentioned before.

firstly i run this code. it runs ok.

% EXTRACT FEATURES FROM AN ARBITRARY FINGERPRINT
clear;
clc; 
close all;

[filename,path]=uigetfile('*.tif','Fingerprints');
flag =1; % Show images. 0 if don't show
filename=strcat(path,filename);
Extract_Features(filename,flag);

then i run this code

this below code i mentioned previously that gives error:

function Extract_Features(filename,flag)
img1 = imread(filename);
if ndims(img1) == 3; img1 = rgb2gray(img1); end  % Color Images
disp(['Extracting features from ' filename ' ...']);
fir=ext_finger(img1,0);
fir=fir(fir(:,3)<5,:);
if flag ==1
    figure;
    imshow(img1);
    hold on
    fir1=find(fir(:,3)==1);
    fir3=find(fir(:,3)==3);   
    plot(fir(fir1,1),fir(fir1,2),'r+');
    plot(fir(fir3,1),fir(fir3,2),'bo');
end
filename2=filename; filename2(end-1)='x'; filename2(end)='t';
save(filename2,'fir','-ascii');
end

[Walter Roberson]

The code line

Extract_Features(filename,flag);

is already running Extract_Features on your behalf. You should not be trying to invoke Extract_Features at the command line without using your script.

[Gurwinder pal singh Bhinder]

i dont understand what you say. kindly ellaborate again

[Walter Roberson]

>> Extract_Features

That is a mistake because you are not telling Extract_Features which file you want to process.

You already designed code to ask the user which file to process and then to automatically call Extract_Features to do the work on the file, so you should be running that code instead of running Extract_Features directly. So at the command line, give the name of the file that you wrote that starts with the line

% EXTRACT FEATURES FROM AN ARBITRARY FINGERPRINT

For example if that code is stored in fingee.m then at the command line give the command

>> fingee

[Gurwinder pal singh Bhinder]

ok. so, i dont need to run separately extract_features.m, it will run when i run other first code . thats what i understand

[Gurwinder pal singh Bhinder]

thank you for your help

[Walter Roberson]

Right.