1.7 Warnings and Messages
Mathematica TE usually goes about its work silently, giving output only when it has finished doing the calculations you asked for.
However, if it looks as if Mathematica TE is doing something you definitely did not intend, Mathematica TE will usually print a message to warn you. There is a list of standard Mathematica TE messages available as a Wolfram Research technical report, Mathematica Warning Messages.
The most common causes of "bugs" are spelling mistakes.
In[1]:= Pqrt[16]
Out[1]= 
The square root function should have only one argument. Mathematica TE prints a message to warn you that you have given two arguments here.
In[2]:= Sqrt[4, 5]
Out[2]= 
Each message has a name. You can switch off messages using Off.
In[3]:= Off[Sqrt::argx]
The message Sqrt::argx has now been switched off, and will no longer appear.
In[4]:= Sqrt[4, 5]
Out[4]= 
This switches Sqrt::argx back on again.
In[5]:= On[Sqrt::argx]
Functions for controlling message output.
Other Mathematica functions related to messages. (See Section 3.2.)
