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katteri
03-07-2005, 04:00 PM
Equation (1) and (2) are arithmetic expressions of numbers.
uation (1) is sum of Xn numbers.
Equation (2) is sum of Xij numbers, where i =1....i and j=1.....j

Is it possible to represent equation (3 ) in a condensed form.as i have represented sum of numbers by sigma.

http://img1.imagevenue.com/loc241/th_1e6_eqn.JPG (http://img1.imagevenue.com/img.php?loc=loc241&image=1e6_eqn.JPG)


Note:
Xij: Can take any values and are independent of others, there is no relationship between the values (so representation by factorial has to be discarded...)

atlast: Xij is decimal.:

For example if i have 4 values in equation (3): which are x11=.9,x12=.9,,x21=.8,x22=.98
the output

prasan8181
03-07-2005, 04:49 PM
If a compact representation is what you want, do this: There is a symbol used to denote multiplication: It looks like this:

-------------
| |
| |
| |

Yup. Just like the PI symbol. So, put this in the place where you put summation, and you are done.

By the way, your equation (2) would require two summations, one over i and one over j.

(If you assume that your x_ij are tensors, then you can as well omit the summation :ahha: which is what Einstein did)

katteri
03-07-2005, 05:11 PM
Thanks Prasan.
YEah i mised it in second ...

vasan
03-07-2005, 05:19 PM
http://img3.imagevenue.com/loc298/th_255_k1.jpg] (http://img3.imagevenue.com/img.php?loc=loc298&image=255_k1.jpg)

http://mathworld.wolfram.com/EinsteinSummation.html

v-

katteri
03-07-2005, 05:48 PM
http://mathworld.wolfram.com/Product.html

Vasan G.
ithu than nan kettathu

prasan8181
03-07-2005, 10:13 PM
The convention was introduced by Einstein (1916, sec. 5), who later jested to a friend, "I have made a great discovery in mathematics; I have suppressed the summation sign every time that the summation must be made over an index which occurs twice..."

Ah, the old Albert. ;)

vasan
03-07-2005, 10:16 PM
http://mathworld.wolfram.com/Product.html

Vasan G.
ithu than nan kettathu

athey thaan naanum type panni image aa potten.. but didnot show.. :Ksp: :Ksp:

'Nyways.. glad your questions are answerd.. :P

:b:

v-

Shy
03-08-2005, 12:28 AM
:dance: :dance: :dance: :dance: :dance: :dance:

Happy that your questions were answered.. me bad :oops: :oops:

Shy