# how can i convert from one value to multi values

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work wolf on 19 Jun 2022
Commented: work wolf on 23 Jun 2022
how can i replace value of
alpha = 0.5
by multi values as
alpha =[0.1 0.3 0.5 0.6 0.66 0.9 1]
in the following code:
alpha = 0.5;
u0 = 0;
a_k = @(k) (k + 1)^(1 - alpha) - (k)^(1 - alpha);
n = 100;
a = 0;
b = 1;
h = (b - a) / n;
t = a:h:b;
f = @(t,u) (-u.^4) + (gamma(2*alpha+1) ./ gamma(alpha+1) ) .* (t.^alpha) - ...
(2./gamma(3 - alpha) ) .* (t.^(2 - alpha)) + (t.^(2*alpha) - t.^2).^4;
up = zeros(1, n);
uc = zeros(1, n);
zp = zeros(1, n);
uc = zeros(1, n); % ??? is this your "u"?
C = gamma(2 - alpha) * h ^ alpha;
for ni = 1:n
up(ni) = a_k(ni - 1) * u0;
for k = 1:ni - 1
up(ni) = up(ni) + (a_k(ni - 1 - k) - a_k(ni - k)) * uc(k);
end
zp(ni) = C * f(t(ni), up(ni));
uc(ni) = up(ni) + C * f(t(ni), up(ni) + zp(ni));
end
fprintf('%g\n', up(1:20))
##### 2 CommentsShowHide 1 older comment
work wolf on 20 Jun 2022

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### Accepted Answer

Image Analyst on 20 Jun 2022
Try this:
% Define all the alphas that we want to use.
allAlpha =[0.1 0.3 0.5 0.6 0.66 0.9 1]
% Iterate the code for each value of alpha.
for kk = 1 : length(allAlpha)
alpha = allAlpha(kk);
% Existing code below:
u0 = 0;
a_k = @(k) (k + 1)^(1 - alpha) - (k)^(1 - alpha);
n = 100;
a = 0;
b = 1;
h = (b - a) / n;
t = a:h:b;
f = @(t,u) (-u.^4) + (gamma(2*alpha+1) ./ gamma(alpha+1) ) .* (t.^alpha) - ...
(2./gamma(3 - alpha) ) .* (t.^(2 - alpha)) + (t.^(2*alpha) - t.^2).^4;
up = zeros(1, n);
uc = zeros(1, n);
zp = zeros(1, n);
uc = zeros(1, n); % ??? is this your "u"?
C = gamma(2 - alpha) * h ^ alpha;
for ni = 1:n
up(ni) = a_k(ni - 1) * u0;
for k = 1:ni - 1
up(ni) = up(ni) + (a_k(ni - 1 - k) - a_k(ni - k)) * uc(k);
end % of k loop
zp(ni) = C * f(t(ni), up(ni));
uc(ni) = up(ni) + C * f(t(ni), up(ni) + zp(ni));
end % of ni loop
fprintf('%g\n', up(1:20))
end % of kk loop
##### 6 CommentsShowHide 5 older comments
work wolf on 23 Jun 2022
@Image Analyst thank you so much again. it's done with edite
up = zeros(kk, n+1);
uc = zeros(kk, n+1);
zp = zeros(kk, n+1);
before loop (for kk = 1 : length(allAlpha) ) and replace kk by length(allAlpha).
Best regards

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### More Answers (1)

Ayush Kumar Jaiswal on 19 Jun 2022
Edited: Ayush Kumar Jaiswal on 19 Jun 2022
You want to calculate that function at different values of alpha, it can done using
arrayfun (func, arr);
##### 1 CommentShowHide None
work wolf on 20 Jun 2022

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