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Topic: Vector definition using variables
Replies: 4   Last Post: Dec 7, 2012 6:55 AM

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 dpb Posts: 9,850 Registered: 6/7/07
Re: Vector definition using variables
Posted: Dec 5, 2012 2:08 PM

On 12/5/2012 12:14 PM, Matt wrote:
>
> I would expect the value of vect1 to be 1x330.
>
> What I don't understand is that using the tstep formula, it gives me
> something like 0.9 (300/330).
>
> My problem is that I have defined a final_time value to top the
> simulation. But it happens that the value of d for example has more
> columns than the vector time. For example d can be 1x400 and time still
> stays 1x301.
>
> So I need to "rescale" the vector time, and that's why I want to use a
> different time step, so both vectors can have the same length and can be
> plotted together.

Well the problem w/ the above ratio is it is simply the ratio of the two
vector lengths but not scaled by the time span (either based on the full
length or that of the initial vect1). So, you computed a ratio of two
lengths but didn't adjust the dT to go along with it.

>> tstep=0.1;f_time=30;vect1=0:tstep:f_time;
>> tstep=tstep*300/330;
>> vect2=0:tstep:f_time;
>> length(vect2)

ans =
331
>>

You might look at

doc linspace

--

Date Subject Author
12/5/12 Matt
12/5/12 Steven Lord
12/5/12 Matt
12/5/12 dpb
12/7/12 Matt