Is there any possible GetCellFormula faster?

[ShowerBandV]

Description
A sheet which has 4600 rows and 55 cols, and some cols have formulas,I want to get them,it seems no problem but the time cost is very large,I want to know whether excelize can solve this.

here is demo code and file

func TestGetFormulas(t *testing.T) {
	file, err := excelize.OpenFile("4600Formulas.xlsx")
	if err != nil {
		panic(err)
	}
	begin := time.Now()
	for col := 0; col < 55; col++ {
		for row := 0; row < 4600; row++ {
			axis := AxisEncode(col, row)
			_, err := file.GetCellFormula("Sheet1", axis)
			if err != nil {
				panic(err)
			}
		}
	}
	fmt.Printf("GetCellFormula time cost:%dms", time.Since(begin).Milliseconds())
}

4600Formulas.xlsx

[HZL3151904214]

共享函数的实现有问题，理论上共享函数应该单独存储一个共享函数的索引结构吧，不应该为了获取共享函数的表达式在多遍历一次m * n，这样一旦是共享函数就需要m * n * m * n，性能太差了。作者这块有规划优化下？

[xuri]

Thanks for the feedback. If you would like to create a pull request for this, that would be great.