Re: Numbers in arbitrary bases

*To*: mathgroup at smc.vnet.net*Subject*: [mg13790] Re: [mg13734] Numbers in arbitrary bases*From*: MJE <evans.nospam at gte.net>*Date*: Fri, 28 Aug 1998 04:18:16 -0400*Organization*: None*References*: <199808190538.BAA00630@smc.vnet.net.>*Sender*: owner-wri-mathgroup at wolfram.com

In my computer programming work, I invariably use inferior tools to convert between hex, decimal, and binary formats. Actually, the little calculator that comes with MS Windows under Accessories has this capability in Scientific view mode. It is easier for me than Mathematica. Using Mathematica to simulate computer math has another quirk, in that an arbitrary hex number in 2's complement can be interpreted as signed or unsigned, depending on the word size of interest. It would be convenient to tell Mathematica what is the word size of a given hex number and then have it left-pad with zero bits or one bits as appropriate. When the word size is undefined, it is very hard to manipulate hex numbers. Each number can have its own word size (or compiler type if you please). Another problem with Mathematica is that there is no "number input" widget. This widget should be able to handle multiple bases whenever it is developed. I have written my own custom C++ code (MFC) for this and it is not too hard. My code does the left-padding stuff, i.e. if you type 0xFF into a signed hex 16-bit field it assumes you mean 0xFFFF. If the field type is unsigned, it assumes 0x00FF. Mark Remove ".nospam" to reply Jon Prudhomme wrote: > > Hello, > > I am looking for a way to work in arbitrary bases in Mathematica > without having to use the base^^number and BaseForm[number,base] > functions every time I wish to input or display a number. Is there > anyway to change Mathematica's 'default' base? > > Also, has anyone else had trouble getting the base^^number function to > work when base is an expression and not a number?

**References**:**Numbers in arbitrary bases***From:*Jon Prudhomme <prudhomj@elwha.evergreen.edu>