How do i can write a for loop inside a for loop?

I am working on a fluid flow problem i want to find the velocity, Reynolds, darcy friction factor and the loss head.

However, the velocity is function of darcy friction factor and the loss head.

Reynolds and flow rate are functions of velocity.

darcy friction should be calculated by a for loop using Colebrook equation.(1 loop)

I don't have any of: velocity, flow rate, loss and darcy friction factor.

[Image Analyst]

If you don't have any of the values, or ranges of values, then you really can't do anything, can you. Not even a loop.

To have a for loop inside a for loop, you can do

for k1 = k1Start : k1Stop
    for k2 = k2start : k2stop
        % Some code...
    end
end

[Hussein Rida]

can i share my code?

[Hussein Rida]

function [f,v,Re,q,com] =Darcy_Weisbach_fittingsa(k,total_loss,pump_loss,l,d,r,rho,viscosity)
f0=0.04;
f=zeros(size(total_loss));
com0=12;
for i=1:100
    v0=sqrt(((2*9.81*(total_loss+pump_loss-com0))/((f0*(l/(d/1000)))+k)));
    Re0=(rho*v0*(d/1000))/(viscosity*0.001);% Convert viscosity from centipoise to Kg/m.s
    q0=v0*(pi*(0.10226^2)*0.25);
    v(i)=v0;
    Re(i)=Re0;
    q(i)=q0;
    for j=1:length(Re(i))
    f0=(-2*log10((r/d)/3.7+2.51/Re(j)/sqrt(f0)))^-2;% used for smooth pipes and fully rough pipes
  f(j)=f0;
    end
         com0=((q(i)*13.3)/(12*1000))^2;
         com(i)=com0;
end
v=v(i)
Re=Re(i)
q=q(i)
com=com(i)
if Re<2000
    f=64/Re
end
end

[darova]

How to run your code