Unless i'm wrong, there is no integrated command in the 50G to calculate a controllability matrix.
This can be done for example in Matlab with the 'ctrb' command. Here is a general Rpl program to do this :
«
-> a b
«
« a n ^ b * TRN »
'n'
0
a SIZE HEAD 1 -
1
SEQ
« AUGMENT » STREAM TRN
»
»
'Ctrb' STO
This new command works either in exact, approx or symbolic mode.
But perhaps is there another way to do this ?
Here are interesting explanations and exercices about controllability :
http://www.control.utoronto.ca/~broucke/ece557f/Lectures/ch3.pdf
My examples are taken from the prévious link ( University of Toronto) and 3.1.3 case is interesting about the 50G Cas power
(exact mode, Real) :
3.1.1
-----
[[ 0 1 0 0 ]
['-K/M1' 0 'K/M1' 0 ]
[ 0 0 0 1 ]
[ 'K/M2' 0 '-K/M2' 0 ]]
[[ 0 0 ]
['1/M1' 0 ]
[ 0 0 ]
[ 0 '1/M2']]
Ctrb
->
[[ 0 0 '1/M1' 0 0 0 '-(K/M1^2)' 'K/(M2*M1)' ]
[ '1/M1' 0 0 0 '-(K/M1^2)' 'K/(M2*M1)' 0 0 ]
[ 0 0 0 '1/M2' 0 0 'K/(M2*M1)' '-(K/M2^2)' ]
[ 0 '1/M2' 0 0 'K/(M2*M1)' '-(K/M2^2)' 0 0 ]]
RANK
-> 4 @ The system is controllable (Rank = n)
3.1.2
-----
[[0 1 0 0]
['-K/M1' 0 'K/M1' 0]
[ 0 0 0 1]
['K/M2' 0 '-K/M2' 0]
]
[[0]
['-1/M1']
[ 0]
['1/M2']]
Ctrb
->
[[ 0 '-1/M1' 0 '(K*(M1*M1)+K*(M2*M1))/(M2*M1*(M1*M1))' ]
[ '-1/M1' 0 '(K*(M1*M1)+K*(M2*M1))/(M2*M1*(M1*M1))' 0 ]
[ 0 '1/M2' 0 '(-(K*(M1*M2))-K*(M2*M2))/(M2*M2*(M1*M2))' ]
[ '1/M2' 0 '(-(K*(M1*M2))-K*(M2*M2))/(M2*M2*(M1*M2))' 0 ]]
RANK
-> 2 @ The system is not controllable (Rank <> 4)
3.1.3
-----
[[-1 1]
[0 -2]]
'A' STO @ use Matrix writer
[[0] [1]]
'B' STO
A IDN 's' * A - 1/x @ (s.I -A)^(-1)
FACTOR @ Factorise
->
[[ '1/(s+1)' '1/((s+2)*(s+1))' ]
[ 0 '1/(s+2)' ]]
A 't' * << EXP >> DIAGMAP @ e^(At)
->
[[ '1/EXP(t)' '(-EXP(t)+EXP(2*t))/(EXP(2*t)*EXP(t))' ]
[ 0 '1/EXP(2*t)' ]]
'eAt' STO @ or use DUP/ SWAP after
eAt B * B TRN * eAt TRN * @ Wc(t)
->
[[ '(-EXP(t)+EXP(2*t))*(-EXP(t)+EXP(2*t))/(EXP(2*t)*EXP(t)*(EXP(2*t)*EXP(t)))' '(-EXP(t)+EXP(2*t))/(EXP(2*t)*(EXP(2*t)*EXP(t)))' ]
[ '(-EXP(t)+EXP(2*t))/(EXP(2*t)*EXP(t)*EXP(2*t))' '1/(EXP(2*t)*EXP(2*t))' ]]
<< {'t' 'T'} | >> MAP @ change t by T
<< 0 SWAP 't' SWAP 'T' Integrate >> MAP @ (*) integrate = symbol Shift TAN
LIN @ Linearize
->
[[ '1/12+-1/2*EXP(-(2*t))+2/3*EXP(-(3*t))+-1/4*EXP(-(4*t))' 12+-1/3*EXP(-(3*t))+1/4*EXP(-(4*t))' ]
[ '1/12+-1/3*EXP(-(3*t))+1/4*EXP(-(4*t))' '1/4+-1/4*EXP(-(4*t))' ]]
(*) or, if you don't want to use 'blind' stack manipulation :
<< -> f 'Integrate(0,t,f,T)' >> MAP
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