Variable name length is not limited. Mathcad allows using all the symbols of the Latin alphabet, numbers, greek symbols and a number of special symbols: prime, infinity sigh, underscore, percent sign, lower index in the variable name.
Mathcad editor can identify capital and small letters, also inscribed. For instance symbols x and x or х and Х are different symbols for the editor. But it is obligatory to follow certain requirements when entering the variable name:
It is possible to use mathematical expressions as variable names, for example: [a+b] or a+b.
In order to enter the lower index, for example Аi, the mathematical pack of Mathcad demands symbol “[” to be entered from the keyboard.To get out of the lower index input regime, one can press the gap key.
In order to define the value of the variable the colon equal symbol “:=”, is in use, it is input with help of hot keys SHIFT + [:] or by pressing the corresponding knob of the tool bar “Calculator” and “Estimation”. In order to display the value of the variable sign of equality “=” is in use, it is input with help of the “hot key” [=] or by pressing the corresponding knob of the tool bar “Calculator” and “Estimation”.