江苏龙网

  1. 首页 > 生活 > >

Mathematica里面咋自定义公式

(* Windows下的文件路径 *)path = $InstallationDirectory \u0026lt;\u0026gt; "\\\\AddOns\\\\Applications\\\\FormulaData\\\\Kernel\\\\downvalues.m";(* 备份后导入程序包 *)backup = path\u0026lt;\u0026gt;".bak";CopyFile;downvalues = Import;(* 设置要添加的公式 *)newformula1 = HoldPattern] :\u0026gt; QuantityVariable}, "UnitDimensions" -\u0026gt; {{"LengthUnit", 1}, {"MassUnit", 1}, {"TimeUnit", -2}}] == (Quantity* QuantityVariable, "Name" -\u0026gt; "primary mass", "PhysicalQuantity" -\u0026gt; "Mass", "CanonicalUnit" -\u0026gt; {HoldForm}, "UnitDimensions" -\u0026gt; {"MassUnit", 1}]* QuantityVariable, "Name" -\u0026gt; "secondary mass", "PhysicalQuantity" -\u0026gt; "Mass", "CanonicalUnit" -\u0026gt; {HoldForm}, "UnitDimensions" -\u0026gt; {"MassUnit", 1}])/ QuantityVariable}, "UnitDimensions" -\u0026gt; {"LengthUnit", 1}]^2;newformulalist = {newformula1};(* 添加公式，导出为文件，重新加载 *)downvalues] = Join], newformulalist];Export;Get(* 恢复原始文件 *)DeleteFile;RenameFile;(* 验证 *)FormulaData -\u0026gt; Quantity, QuantityVariable, "Mass"] -\u0026gt; Quantity, QuantityVariable, "Mass"] -\u0026gt; Quantity}]FormulaData -\u0026gt; Quantity, QuantityVariable, "Mass"] -\u0026gt; Quantity, QuantityVariable, "Mass"] -\u0026gt; Quantity}]大致是这个样子，思路简单操作繁琐没有效率。使用之前先添加自定义公式，需要扩展到其他系统的话文件路径可以用 FileNameJoin 生成。应该有直接操作读入的 Package 的方法，可惜我没找到，期待高人解答了。


    推荐阅读


    上一篇：从事互联网新媒体运营的是咋赚钱的

    下一篇：亚马逊怎样利用 Kindle 广告版获利