Try solver System of linear algebraic equations in Shell Bash

newbieseos · 10-03-2012, 03:49 AM

I want to try solving system of linear algebraic equations in Shell bash but i have any problems Value input is matrix and I dont know how to input matrix in Shell because that is dont support 2-dimensional array Please help me. Thank you so much

pan64 · 10-03-2012, 04:37 AM

you would better try to use awk/perl or another language, bash does not really support it and is hard to implement.

porphyry5 · 10-03-2012, 04:52 AM

Quote:

Originally Posted by newbieseos

I want to try solving system of linear algebraic equations in Shell bash but i have any problems Value input is matrix and I dont know how to input matrix in Shell because that is dont support 2-dimensional array Please help me. Thank you so much

Suppose your matrix is 3x3. As a one-dimensional array this requires 9 cells. So you can compute the one-dimensional array cell corresponding to M[a, b] by M[a*3+b], e.g.

Code:

~ $ x=(1 2 3 4 5 6 7 8 9)
~ $ a=2
~ $ b=2
~ $ echo ${x[$a*3+$b]}   # the 9th cell
9
~ $ a=0
~ $ b=1
~ $ echo ${x[$a*3+$b]}   # the 2nd cell
2

sycamorex · 10-03-2012, 04:55 AM

Another suggestion would be to use Python. It has lots of maths modules.

newbieseos · 10-03-2012, 05:34 AM

Thanks for all your replying

Snark1994 · 10-03-2012, 05:57 AM

Or languages like MATLAB which are designed exactly for things such as this...

hydraMax · 10-05-2012, 10:45 PM

Quote:

Originally Posted by newbieseos

I want to try solving system of linear algebraic equations in Shell bash but i have any problems Value input is matrix and I dont know how to input matrix in Shell because that is dont support 2-dimensional array Please help me. Thank you so much

Abort now before you lose your sanity. Bash sucks at doing anything beside executing independent programs sequentially or tying together I/O streams. In particular, Bash does weird things with arrays that you will find harder to figure out than your original problem.