g_margin returns error for double integrator
Reported by karteek yanumula
BUG DESCRIPTION:
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When the transfer function is just a double integrator 1/s^2, g_margin() gives error. It works fine with other functions.
ERROR LOG:
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!--error 60
Wrong size for argument: Incompatible dimensions.
at line 33 of function g_margin called by :
g_margin(G)
HOW TO REPRODUCE THE BUG:
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s=%s;
G=syslin('c',1/s^2);
g_margin(G)
OTHER INFORMATION:
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