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Topic: how to enter into vector with variables
Replies: 4   Last Post: Nov 7, 2013 1:20 PM

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 dpb Posts: 9,850 Registered: 6/7/07
Re: how to enter into vector with variables
Posted: Nov 7, 2013 1:20 PM

On 11/7/2013 11:53 AM, goatfish wrote:
> how do i create an 11-entry vector x given by
> x=[a, a+1*(0.5), a+2*(0.5)........ a+10*(0.5)]
>
> I know that something like x=1:1:5 gives x=[1,2,3,4,5]. But i am
> confused how to increment something with only some of the variables
> increasing while the others stay the same. i.e 0.5 and a is constant and
> 0:10 is increasing.

And to amplify on how to see someone's solution or to attack in general,
write the algebraic expression you're trying to implement first in as
general a form as can--

x=[a+0*(0.5), a+1*(0.5), a+2*(0.5)........ a+10*(0.5)]
= a*[0*(0.5), 1*(0.5), 2*(0.5)........ 10*(0.5)]
= a*0.5*[0, 1, 2 ........ 10]

and the next steps should become apparent. The idea is generic, not
just for the specific problem.

--

Date Subject Author
11/7/13 goatfish
11/7/13 Curious
11/7/13 goatfish
11/7/13 Roger Stafford
11/7/13 dpb