# exception.py - exception definitions for the control package
#
# Author: Richard M. Murray
# Date: 31 May 2010
# 
# This file contains definitions of standard exceptions for the control package
#
# Copyright (c) 2010 by California Institute of Technology
# All rights reserved.
#
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# modification, are permitted provided that the following conditions
# are met:
#
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 
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# 
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#    the names of its contributors may be used to endorse or promote
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#    written permission.
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# $Id: exception.py 225 2012-11-03 21:03:39Z murrayrm $

class ControlSlycot(Exception): 
    """Exception for Slycot import.  Used when we can't import a function
    from the slycot package"""
    pass

class ControlDimension(Exception): 
    """Raised when dimensions of system objects are not correct"""
    pass

class ControlArgument(Exception): 
    """Raised when arguments to a function are not correct"""
    pass

class ControlMIMONotImplemented(Exception):
    """Function is not currently implemented for MIMO systems"""
    pass

class ControlNotImplemented(Exception):
    """Functionality is not yet implemented"""
    pass

# Utility function to see if slycot is installed
def slycot_check():
    try:
        import slycot
    except:
        return False
    else:
        return True
