Automatically retrieving some elements from a list
- To: mathgroup at smc.vnet.net
- Subject: [mg128972] Automatically retrieving some elements from a list
- From: "Eduardo M. A. M. Mendes" <emammendes at gmail.com>
- Date: Thu, 6 Dec 2012 04:58:53 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- Delivered-to: l-mathgroup@wolfram.com
- Delivered-to: mathgroup-newout@smc.vnet.net
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Hello
I wonder whether someone could help to understand what is behind Mathematica syntax. Here is an example:
Control`ZeroPoleGainModel[TransferFunctionModel[s+1,s]]
Control`ZeroPoleGainModel[{{{{-1}}},{},{{1}}},s]
I need to extract some values of it so that the output is
{{-1},{},{1}}
Control`ZeroPoleGainModel[TransferFunctionModel[{{2/(1+s^2),s/(s-1)}},s]]
Control`ZeroPoleGainModel[{{{{},{0}}},{{{-I,I},{1}}},{{2,1}}},s]
The same thing but the output should be
{{{},{0}},{{-l,I},{1}},{2,1}}
Can a function be written to accomplish the above outputs automatically?
BTW, is there a command to see all the functions under Control`?
Many thanks
Ed