Problem in writing code for this profile. Need urgent help

Respected sir

My profile equation is

U = 1./(mu).*(t_o.*(y-delta)+4.*lambda.*sqrt(t_o.*t_e).*(exp(-lamda./(2.*delta)))+t_e.*lambda.*(1-exp(-y./lambda)))

I want to plot U vs Y wih varying the value lamda and delta.

I want to see how the plot U VS Y behaves for different lamda and y value let s take an example

case1

 lamda =0.8 delta 0.6

case 2

 lamda =0.8 delta 0.16

case 3

 lamda =0.5 delta 0.6

i have written taking one arbitary value but it is error my code

 a= 100*(y-(3*(10^-6)));

 b=9.2*10^-6;

 c=exp(-0.5*(10^8)*y);

 d=530*(10^-8)*(1-exp(-y*(10^8)));

 e=b*c;

 u=2*(a+e+d);

[Walter Roberson]

I do not see any lamda in the assignments you posted? I do not see mu, or t_o, or delta, or t_e in the assignments you posted?

It is not clear how a, b, c, d, e, or u fit into your equations?

[Debasis Roy]

In my programme, I have divided it in it parts and also assigned some arbitary value to all constant. I have written each parts with some value and named a,d,e,b,c, & written the final equation

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/29922-why-your-question-is-not-urgent-or-an-emergency

Answer 1

[Walter Roberson]

mu = rand();
t_o = rand();
t_e = rand();

deltavals = [0.6 1.1 1.6];
lambdavals = [0.5 0.6 0.7 0.8];
yvals = -2:0.5:2;
[delta, lambda, y] = ndgrid(deltavals, lambdavals, yvals);

U = 1./(mu).*(t_o.*(y-delta)+4.*lambda.*sqrt(t_o.*t_e).*(exp(-lambda./(2.*delta)))+t_e.*lambda.*(1-exp(-y./lambda)));

volumeViewer(U)

[Debasis Roy]

Sir, please clear me following doubts

1> I have to values in the bracket of mu () in?

2>i am unable to understand use of [delta, lambda, y] = ndgrid(deltavals, lambdavals, yvals);

3> Sir why it is used volumeViewer(U). is it for plotting?

[Walter Roberson]

Minimal brackets version

 mu = rand;
t_o = rand;
t_e = rand;

 deltavals = [0.6 1.1 1.6];
lambdavals = [0.5 0.6 0.7 0.8];
yvals = -2:0.5:2;
[delta, lambda, y] = ndgrid(deltavals, lambdavals, yvals);

 U = 1./mu.*(t_o.*(y-delta)+4.*lambda.*sqrt(t_o.*t_e).*exp(-lambda./(2.*delta))+t_e.*lambda.*(1-exp(-y./lambda)));

Yes, the volumeViewer was just for plotting.

[Walter Roberson]

https://www.mathworks.com/help/matlab/ref/ndgrid.html

You could substitute meshgrid for ndgrid in this case.

[Debasis Roy]

Sir if I write is it ok? but I am not getting the result. As I want different plot of u vs y corresponding to different values of lambda and delta

mu=0.6;

t_o=106;

t_e=156;

   deltavals = [0.6 1.1 1.6];

lambdavals = [0.5 0.6 0.7 0.8];

yvals = 0.3:0.1:1;

[delta, lambda, y] = ndgrid(deltavals, lambdavals, yvals);

U = 1./mu.*(t_o.*(y-delta)+4.*lambda.*sqrt(t_o.*t_e).*exp(-lambda./(2.*delta))+t_e.*lambda.*(1-exp(-y./lambda)))

plot(y,U,'-r')

[Walter Roberson]

"I want different plot of u vs y corresponding to different values of lambda and delta"

Your inputs are y, lambda, and delta. Your output is u. With three inputs and 1 output, you are dealing with 4 dimensional plotting. However, you are trying to use plot(), which is for 2 dimensional plotting (one output for each input.)

In order to plot with three input variables and one output variable, the Mathworks plotting routines available are slice(), isosurface(), and volumeViewer(). You can also look in the File Exchange for vol3d v2 or https://www.mathworks.com/matlabcentral/fileexchange/59161-volumetric-3

[Debasis Roy]

ok, sir thank you for clarifying my doubt. Now I am realizing my fault about this, I have attached one picture for plot i want u vs y plot like this .I am editting it mu=0.6;

t_o=106;

t_e=156;

 deltavals = 0.6 ;

alphavals = [-0.3,- 0.2 ,-0.1,0, 0.1,0.2,0.3 ];

yvals = 0.3:0.1:1;

[ alpha, y] = ndgrid( alphavals, yvals);

U = 1./mu.*(t_o.*(y-delta)+4.*alpha.*sqrt(t_o.*t_e).*exp(- alpha./(2.*delta))+t_e.*alpha.*(1-exp(-y./alpha)))

plot(y,U,'-r')