A computer-implemented system and method for converting the resistances of an array of metal oxide sensors into constituents and concentrations of a multi-component gas provided around the sensor array. The method includes preprocessing the resistances of the sensor array; selecting a model that calculates the constituents and concentrations of the multi-component gas based on the preprocessed resistances; and post-processing the constituents and concentrations of the multi-component gas generated by the selected model to provide the actual constituents and concentrations of the multi-component gas.