Question about defining a math macro
Hi, Can I define a math macro, say \EXP that does the following: 1) \EXP{something} gives me, say E(something) 2) \EXP_a^b{something} gives my E_a^b(something) That is, I want to write a macro that will only be used in the math mode, that does something with its argument. But, I also want it to handle _ and ^ if they are present. The only method that I can think of is to check _ or ^ with \ifnextcharacter and go through all 5 cases (nothing, only _, only ^, _ followed by ^, ^ followed by _) but this seems very inefficient. Is there a better way? Aditya
Aditya Mahajan wrote:
Hi,
Can I define a math macro, say \EXP that does the following:
1) \EXP{something} gives me, say E(something) 2) \EXP_a^b{something} gives my E_a^b(something)
That is, I want to write a macro that will only be used in the math mode, that does something with its argument. But, I also want it to handle _ and ^ if they are present.
The only method that I can think of is to check _ or ^ with \ifnextcharacter and go through all 5 cases (nothing, only _, only ^, _ followed by ^, ^ followed by _) but this seems very inefficient. Is there a better way?
Actually, there is, by using a bit of black magic in the macro definition: \def\EXP#1#{\bgroup\def\EXParg{#1}\doEXP} \def\doEXP#1{\mfunction{E}\EXParg({\rm #1})\egroup} That extra hash mark has the effect of putting everything upto the next explicit left brace into #1. Cheers, Taco
On Sat, 24 Feb 2007, Taco Hoekwater wrote:
Aditya Mahajan wrote:
Hi,
Can I define a math macro, say \EXP that does the following:
1) \EXP{something} gives me, say E(something) 2) \EXP_a^b{something} gives my E_a^b(something)
That is, I want to write a macro that will only be used in the math mode, that does something with its argument. But, I also want it to handle _ and ^ if they are present.
The only method that I can think of is to check _ or ^ with \ifnextcharacter and go through all 5 cases (nothing, only _, only ^, _ followed by ^, ^ followed by _) but this seems very inefficient. Is there a better way?
Actually, there is, by using a bit of black magic in the macro definition:
\def\EXP#1#{\bgroup\def\EXParg{#1}\doEXP} \def\doEXP#1{\mfunction{E}\EXParg({\rm #1})\egroup}
That extra hash mark has the effect of putting everything upto the next explicit left brace into #1.
Wow Taco. This is great. Thanks, Aditya
Aditya Mahajan wrote:
On Sat, 24 Feb 2007, Taco Hoekwater wrote:
Aditya Mahajan wrote:
Hi,
Can I define a math macro, say \EXP that does the following:
1) \EXP{something} gives me, say E(something) 2) \EXP_a^b{something} gives my E_a^b(something)
That is, I want to write a macro that will only be used in the math mode, that does something with its argument. But, I also want it to handle _ and ^ if they are present.
The only method that I can think of is to check _ or ^ with \ifnextcharacter and go through all 5 cases (nothing, only _, only ^, _ followed by ^, ^ followed by _) but this seems very inefficient. Is there a better way?
Actually, there is, by using a bit of black magic in the macro definition:
\def\EXP#1#{\bgroup\def\EXParg{#1}\doEXP} \def\doEXP#1{\mfunction{E}\EXParg({\rm #1})\egroup}
That extra hash mark has the effect of putting everything upto the next explicit left brace into #1.
Wow Taco. This is great.
some applications of this mechanism can be found in the context source code (supp-box etc) Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Sat, 24 Feb 2007, Hans Hagen wrote:
Aditya Mahajan wrote:
On Sat, 24 Feb 2007, Taco Hoekwater wrote:
Aditya Mahajan wrote:
Hi,
Can I define a math macro, say \EXP that does the following:
1) \EXP{something} gives me, say E(something) 2) \EXP_a^b{something} gives my E_a^b(something)
That is, I want to write a macro that will only be used in the math mode, that does something with its argument. But, I also want it to handle _ and ^ if they are present.
The only method that I can think of is to check _ or ^ with \ifnextcharacter and go through all 5 cases (nothing, only _, only ^, _ followed by ^, ^ followed by _) but this seems very inefficient. Is there a better way?
Actually, there is, by using a bit of black magic in the macro definition:
\def\EXP#1#{\bgroup\def\EXParg{#1}\doEXP} \def\doEXP#1{\mfunction{E}\EXParg({\rm #1})\egroup}
That extra hash mark has the effect of putting everything upto the next explicit left brace into #1.
Wow Taco. This is great.
some applications of this mechanism can be found in the context source code (supp-box etc)
Yes, those were parts of the core that I could never understand. Now, I do understand them a little. Thanks, Aditya
participants (3)
-
Aditya Mahajan -
Hans Hagen -
Taco Hoekwater