# Homework Help: Plotting with Matlab

Tags:
1. Feb 18, 2017

### Pouyan

1. The problem statement, all variables and given/known data

I have a function :

and I want to draw :

2. Relevant equations

where T has values : 600, 800, 1000, 1100 And λ:(0,10*^-5] I have to use max function with two values and the solution must not consist of repeating four times of similar snippets of code, one for each curve.The image should be stylish. For example. so the texts may not cut curves, but neatly placed just above the maximum point.
3. The attempt at a solution

This is the way how I start :
F=@(L,T) 3.7415E-16 ./((L.^5).*(exp(0.014 ./(L.*T))-1));
T=[600, 800, 1000, 1100];
L=0:10^-6:10^-5;
[Lm Tm]=meshgrid(L,T);
fm=F(Lm,Tm);
plot(L,fm)
hold on
grid on
[Y I]=max(fm);
plot(L(I),Y,'*')
And I get :
My question is how should I use text function in Matlab to write T for correspond curve

2. Feb 19, 2017

### Pouyan

This how I could develop the code but I fail with one thing !

clear all

clc

F=@(L,T) 3.7415E-16 ./((L.^5).*(exp(0.014 ./(L.*T))-1));

T=[600 800 1000 1100];

L=0:10^-7:10^-5;

[Tm Lm]=meshgrid(T,L);

fm=F(Lm,Tm);

plot(L,fm)

grid on

[Y I]=max(fm);

hold on

plot(L(I),Y,'*')

%text(L(I),Y,'T= ')

hold on

for i=1:1:4

S=['T= ',num2str(T(i))]

N = L(I)-1.E-7;

G = Y+5.E8;
text(N,G, S)
end

I get this image as result :