1. A robot control algorithm constructing apparatus that constructs a control algorithm controlling the operation of a robot having at least one joint connecting two members to make the relative position or attitude between the two members variable, comprising: a definition storage section that stores a definition of a neuron to produce an output with an analogue lag including a zero lag based on an input; a control algorithm generation section that generates a control algorithm with coefficient values undetermined, constructed by a recurrent neural network having plural neurons and including at least one lag neuron to produce an output with an analogue lag excluding a zero lag in the plural neurons, in which there is a loop of signal flow, employing the definition stored in the definition storage section; and a coefficient value determination section that determines a coefficient value for the control algorithm generated by the control algorithm generation section.