本研究的主旨，在探討數種以搜尋最小區域真圓度值為目標的演算法其間的差異。文中將先說明四種利用幾何圖形估算真圓度的演算方法，接著以電腦模擬產生不同類型的資料輸入，繼而執行各演算法推估真圓度值。經由觀察搜尋過程的效率、收斂的程度與結果精確度，瞭解各演算法的適用情形。資料的類型變化包含資料點的分佈範圍、分佈形式，資料點數目的多寡、搜尋的起點位置、誤差與半徑的比值等方式。此外，本研究同時利用數值分析中的牛頓法計算真圓度值，以建立共同參考的比較基準。

The objective of this research is to investigate several algorithms using geometrical graphics to evaluate circularity under the criteria of minimum zone circles. In this work, the detailed procedures of four different algorithms are studied first and the corresponding computation codes are written next. Then many groups of pseudo measurement data are generated through random functions. Finally, measurement data are input to codes and output circularity are examined. The comparisons among these four algorithms are based on computation speed, capability of convergence and accuracy of the results. The testing data cover different ranges, distributions, numbers, starting points of searching process, and ratios between the error and radius. In addition, the circularity estimated by a numerical analysis method is used as the benchmark for comparison.

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