How to get my while loop to skip into the next loop?

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Apologies for the long code in advance. I'm unsure how to get my first while loop (within the initial while loop) to skip onto the next one. To give you a back ground, this is to represent pumping and refill of fluid transfer, so heigh (h) changes with time (t). I want it to pump for the time calculated (tp), and then once it reaches this, skip to refilling (for time trf). This should be done until the height in a feed tank = 0 (larger while loop). When I run it, it does not skip to the second while loop. Hence, this pump then refill cycle should continue to loop around a number of times. Any advice how I can get this? Code is below. Thanks in advance.
%Input initial conditions
Pi=300000;
g=9.81;
RHO=1400;
Po=101325
Dt=0.05;
At=pi*(Dt.^2)/4
Df=6;
Af=pi*(Df.^2)/4
Dpc=1;
Apc=pi*(Dpc.^2)/4
Cd=0.975;
Cp=0.7
hpc=1.71;
hinitial=1.71;
hfinitial=6;
%All details up to this point must be input by user
%Calculation of further initial conditions
Ptinitial=RHO*g*hfinitial
Qiinitial=Cd*At*sqrt((2*(Pi+(RHO*g*hinitial)-Ptinitial)/RHO))
Qoinitial=(At/(sqrt(1-Cp)))*sqrt(2*((Pi-Po)/RHO))
QHinitial=Qoinitial-Qiinitial
Qrfinitial=Cd*At*sqrt(2*g*(hfinitial-hinitial))
tpinitial=sqrt(2/g)*(Apc/(Cd*At))*(hpc/(2*sqrt(((Pi-Ptinitial)/(RHO*g))+(hpc/2))))
trfinitial=sqrt(2/g)*(Apc/(Cd*At))*(hpc/(2*sqrt(hfinitial-(hpc/2))))
%Assigning an empty matrix for all values to be calculated
RFDoutput=zeros(10000,9)
RFDoutput(:,1)=1:10000
t=RFDoutput(t,1)
RFDoutput(1,1)=0
RFDoutput(1,3)=hinitial
RFDoutput(1,2)=hfinitial
RFDoutput(1,4)=Ptinitial
RFDoutput(1,5)=Qiinitial
RFDoutput(1,6)=tpinitial
RFDoutput(1,7)=0 %Qrf
RFDoutput(1,8)=QHinitial
%Values recorded
tinitial=1
t=1
while hfinitial>0
while round(tinitial) <= RFDoutput(t,1) < round(tinitial+tpinitial) %could put as if/while statement, while tinitial=<t<tpinitial
RFDoutput(t+1,1)=t %Input into matrix
hdecH(t)=Qiinitial/Af %Input into matrix
hdecpc(t)=Qiinitial/Apc
hnewH(t)=hfinitial-hdecH(t)
RFDoutput(t+1,2)=hnewH(t)
hnewpc(t)=hinitial-hdecpc(t)
RFDoutput(t+1,3)=hnewpc(t) %Input into matrix
hinitial=hnewpc(t)
hfinitial=hnewH(t)
Pt(t)=RHO*g*hfinitial
RFDoutput(t+1,4)=Pt(t) %Input into matrix
Qi(t)=Cd*At*sqrt(2*((Pi+(RHO*g*hinitial)-Pt(t))/RHO))
RFDoutput(t+1,5)=Qi(t) %Input into matrix
Qinitial=Qi(t)
QH(t)=Qoinitial-Qi(t)
RFDoutput(t+1,8)=QH(t)
tpintitial(t)=sqrt(2/g)*(Apc/(Cd*At))*(hpc./(2*sqrt(((Pi-Pt(t))./(RHO*g))+(hpc./2))))
RFDoutput(0:tpinitial+1,6)=tpinitial
trfinitial=t+tpinitial
t=t+1
end
while round(tpinitial+1) < RFDoutput(t,1) <= round(tpinitial+1+trfinitial)
RFDoutput(t+1,1)=t
hdecH(t)=Qrfinitial/Af
hnewH(t)=hfinitial-hdecH(t)
hfinitial=hnewH(t)
RFDoutput(t+1,2)=hnewH(t)
hincpc(t)=Qrfinitial/Apc
hnewpc(t)=hinitial+hincpc(t)
hinitial=hnewpc(t)
RFDoutput(t+1,3)=hnewpc(t)
Pt(t)=RHO*g*hfinitial
RFDoutput(t+1,4)=Pt(t)
Qrf(t)=Cd*At*sqrt(2*g*(hfinitial-hinitial))
RFDoutput(t+1,7)=Qrf(t)
trfinitial(t)=sqrt(2/g)*(Apc/(Cd*At))*(hpc./(2*sqrt(hfinitial-(hpc./2))))
RFDoutput(t+1,9)=trfinitial(t)
tinitial=t
t=t+1
end
end

Answers (1)

Geoff Hayes
Geoff Hayes on 17 Mar 2017
ranbo95 - your condition in your while loop seems suspect
while round(tinitial) <= RFDoutput(t,1) < round(tinitial+tpinitial)
I don't think that this is a valid statement and that you should be using
while round(tinitial) <= RFDoutput(t,1) && RFDoutput(t,1) < round(tinitial+tpinitial)
instead. Consider the following
4 < 3 < 2
what should the answer be? 4 is clearly not greater than 3 so this is false (0). But 0 is less than 2 so the above statement is true (1).
Contrast this with
4 < 3 && 3 < 2
which returns false (as expected).
Please clarify what your conditions should be. The same is true for the other inner while loop.

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