Generating a matrix based on an equation with conditions

Hello,

Are there any way to do the following?

I want to generate a n*1 matrix based on this equation:

M = T1*G*Z1 - T2*G*Z2 + F - C*P

all variables are known and constant but with the following conditions:

1) F is zero in the entire column, excpet at a certain row, its equal to a constant number

2) From Row 1 to a certain row, this term (T2*G*Z2) is zero, for example until row 200. While from row 201 to the end, the previous term has constant value but this term (T1*G*Z1) is zero.

Thanks

[Matt J]

How can M be 1*n if F is a column vector?

[A Aln]

Sorry, M is the nx1 matrix:

[

1

2

3

4

5

.

.

n

]

and the numbers should be calculated based on this equation:

T1*G*Z1 - T2*G*Z2 + F - C*P

all of them are known, but based on the row, some of them will be zeros as mentioned in the above conditions.

the matrix should look like this

[

1

1

2 < in this row only, F = constant number

1 < till here, this term (T2*G*Z2) is zero and this term (T1*G*Z1) is constant number

3 < starting from here, this term (T1*G*Z1) is zero and this term (T2*G*Z2) is constant number

3

3

3

]

Sorry for the ambiguityHope it's clear now

[Matt J]

OK, but what then is the problem? If everything on the right hand side is known, then it should be straightforward to calculate M.

[A Aln]

Im new to the matlab, I don't know how to make the conditions, I tried to do that with if statement but it not works for matrices

[Guillaume]

If is most likely not needed.

What are the size of all the variables (T1, G, etc.)?

If they are not scalar variables did you mean * or .* for the multiplications?

[A Aln]

Yes I mean Multiplication, My problem is to make the conditions

if row 50 onward, change the value from 1 to 2

I can change single value by using this for example

A(5,1)=5;

But how can I change any number below this row

Answer 1

[Matt J]

For example,

>> A=zeros(10,1);  A(1:5)=4; A(6:10)=3

A =

     4
     4
     4
     4
     4
     3
     3
     3
     3
     3

[A Aln]

thank you so much, that what I did before, somehow horrible

r1 = (dH*grav*delz) - (accm*pi);
r2 = -(dB*grav*delz) - (accm*pi); %% The eqn

RR = zeros(x*y*z,1);

    RR(1:x*y,1:1)=r1;
    RR((x*y)+1:x*y*z,1:1)=r2;
    RR(well,1)=RR(well,1)+q;

the variables are different and not defined here bcs its part of big code, Again I really appreciate your help