added try block to handle potentially singular matrix
added try block to handle potentially singular matrix

faroit/mir_eval,urinieto/mir_eval,mrgloom/mir_eval,craffel/mir_eval,bmcfee/mir_eval,faroit/mir_eval,rabitt/mir_eval,bmcfee/mir_eval,craffel/mir_eval,rabitt/mir_eval,mrgloom/mir_eval,urinieto/mir_eval