How to insert values from a for loop into an array?

I have to insert values from a for loop into an array, but can't get it to work as the loop variable starts at 0. I have tried the two following approaches, but neither work. Any advice or critisism would be very helpful.

Attempt 1 -

a = 500
b = 1000

for i=0:0.05:2
    elements = a * i 
    area(i) = b + elements   
end

Attempt 2

a = 500 
b = 1000
area = [ ];

for i=0:0.5:2
    
    elements = a*i
    area = [b + elements]
end

Attempt 1 throws up an error message while attempt 2 just doesn't insert the values into an array. Any help would be appreciated. Thank you!

Answer 1

[madhan ravi]

Remember matlab index starts from one not from zero!

Without Loop (faster) :

a = 500
b = 1000
i=0:0.05:2;
elements = a * i ;
area = b + elements  ; 

With Loop :

First method:

a = 500;
b = 1000;
ctr=1;
i=0:0.05:2;
area=zeros(1,numel(i)); % preallocate
for i=i
    elements = a * i ;
    area(ctr) = b + elements ;
    ctr=ctr+1;
end

Second method:

a = 500;
b = 1000;
ctr=1;
i=0:0.05:2;
area=zeros(1,numel(i)); % preallocate
for k=1:numel(i)
    elements = a * i(k) ;
    area(k) = b + elements  ; 
end

[Koalaclo]

Thank you! It worked wonderfully

[madhan ravi]

Anytime :)

[Rolwyn Cardoza]

Hello all, Please help me, I want to append all the values of q into a matrix and store it. The first row must contains all values of 'q' corresponding s1 total 6 rows and the coloumns must be equal to r = 10. Please help . Reach out if the question is not clear

clear

NeuberaData=[0.34 .48 .62 .76 .9 1.03 1.17 1.31 1.45 1.59 1.72;.66 .46 .36 .29 .23 .19 .14 .10 .075 .05 .03];

ND=NeuberaData;

qval=zeros(1,18);

Strength_set = ND(1,:)';

Notch_sense_const= ND(2,:)';

c=polyfit(Strength_set,Notch_sense_const,3);

for s= .3:.35:1.7

for r=1:.5:5

q= 1/ (1+(polyval(c,s))/sqrt(r));

qval(q)

end

end

[Bharath Kumar Musuadhi Rajan]

Thanks a lot! The pandas like 'no for-loop' operation reduced the calculation time from minutes to instant!

Answer 2

[Govardhan K]

a = 500;

b = 1000;

ctr=1;

i=0:0.05:2;

area=zeros(1,numel(i)); % preallocate

for i=i

elements = a * i ;

area(ctr) = b + elements ;

ctr=ctr+1;

end