Excel Formula Help

[aejaz]

Hello Group

i have this rather simple equation , but cant seem to figure out how
to write it in excel

x1=x2=x3=x4=x5=x6=x7=x8=x9=x10

These are just initial values.The formula is a part of a linear
program. so when i solve it using solver , the values can change to
satisfy whatever constraints.

But when the values change, i have to make sure ,for example , that
if x1 = 10 , all the other variables are 10 .

When i write the equation "as is" in excel, it gives me something
like "FALSE".

i could do this manually, but my problem has more than 15 such
equations.

Could you suggest any ideas please?

thanks
aejaz

 

[GB]

How about using Solver to put the value you want in X1
Then have in cell X2 =X$1
Then copy that down to X3 to X10

(I am assuming that your coefficients are in cells X1 to X10)

Geoff

 

[Tom Ogilvy]

=And(X1=X2,X1=X3,X1=X4,X1=X5,X1=X6,X1=X7,X1=X8,X1=X9,X1=X10)

will test if all the cells are equal.

In you formula

assume X9 does equzal x10, then that evaluates to True. Next you formula
would test is X8=True

which would probably be false and the end result would be false.

 

[Harlan Grove]

i have this rather simple equation , but cant seem to figure out how
to write it in excel

x1=x2=x3=x4=x5=x6=x7=x8=x9=x10

...

Assuming all these cells are numeric, the most compact way to test that they're
all exactly equal would be

=DEVSQ(X1:X10)=0

To check that they're all 'effectively' equal, try

=DEVSQ(X1:X10)<1e-12

Replace 1e-12 with a value 'small enough' that you'd consider any variation from
zero to be negligible.