f

#### MatLab coding help needed for basic engineering problem

```Hiya,
i've been trying to figure out a way to create a code to
differentiate, integerate and plot the results for a fluid mechanics
problem and would really appreciate any sort of help that i can get.

The problem's about volume-flow through a pump. What i'm meant to do
is make a GUI through GUIDE and have 3 m-files which can load data
from 2 excel files. the excel files contain 2 columns of Q(volume
flow) and time and numerous rows of values taken at different time
intervals. What i'm supposed to do is create three m-files to
determine:

a.	The change of volume flow with respect to time of the fluid in the
pump i.e dq/dt.

b.	The volume of fluid entering the hydraulic circuit
/
|
| Q dt
|
/

(integrate Q with respect to t)

c.	A function file that determines the difference in the volume of
fluid in this system and a similar system without a leak, which means
the 2 data sets in the 2 excel files. they have been sampled at
different rates so i need to interpolate them as well.

And in the end, plot all a, b, and c with respect to time. The
problem is, i find the derivative of Q with respect to t throw
diff(q)./diff(t)...which ultimately caused the resulting dataset to
have one element less than q or t, and thus, i cant plot it against
t. how do i add another element to diff(q)./diff(t)? i tried using
size(dqdt) = [1001,1] => adding one more element to the set but it
doesnt accept it (dqdt is diff(q)./diff(t)).

What should i do? i believe this would be fairly basic stuff but i'm
a beginner and i would really appreciate some help.

Thanks,
``` 0 4/8/2007 1:13:04 AM comp.soft-sys.matlab  211264 articles. 26 followers. 0 Replies 957 Views Similar Articles

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