Re: Programming
- To: mathgroup at smc.vnet.net
- Subject: [mg2839] Re: [mg2819] Programming
- From: Richard Mercer <richard at seuss.math.wright.edu>
- Date: Sat, 23 Dec 1995 03:19:48 -0500
Jack,
Here is some code that will do what I think you want.
The first step is to create a command that checks for error messages
and undesirable outcomes. I'll call it IntegrateG.
The two Print commands are there just to take up space where your code
will go. If you don't care about error messages, you don't need the
Check command, just use res = Integrate[items].
IntegrateG[items__]:=
Module[{res},
res =
Check[
Integrate[items],
(* error-handling code *)
Print["Error"]
];
If[Head[res] === Integrate,
(* your code here *)
Print["Failure"];
res,
res
]
];
This will work fine. But suppose you want it to automatically replace
Integrate? Here's how:
$Pre = (# /. Integrate->IntegrateG)&;
Now give it a try:
In[5]:=
Integrate[Sqrt[BesselJ[0,x]],x]
Failure
Out[5]=
Integrate[Sqrt[BesselJ[0, x]], x]
Richard Mercer