1. A control method for an analyzation apparatus to perform a stress analysis simulation in accordance with analysis condition data as mesh density, comprising: a target model acquisition step of acquiring analysis target model data which is target of the stress analysis; a condition model generation step of generating analysis condition model data by assigning analysis condition data as mesh density to each region of a three-dimensional solid model represented with the analysis target model data; an analysis step of performing the stress analysis simulation in accordance with the analysis condition model data generated in the condition model generation unit; a result model generation step of generating analysis result model data which have both of first visual appearance indicating the mesh density which assigned to each region of the three-dimensional solid model, the first visual appearance expressed by transparency, and second visual appearance indicating a stress distribution as the result of analysis in the analysis step, the second visual appearance expressed by color; a display step of displaying the three-dimensional solid model represented with said analysis result model data; and a repeating step of repeating the performing in the analysis step, the generating in the result model generation step, and the displaying in the display step, in accordance with new analysis condition data.