From help-octave-request  Mon Jun 21 07:14:34 1993
Subject: norm problem
From: leus at gaserv dot fhp dot fgan dot de (Ludger Leushacke)
To: help-octave
Cc: leus at fganffm dot ffm dot fgan dot de
Date: Mon, 21 Jun 93 13:13:01 GMT


Hello again !

Thanks for your prompt and accurate answer to my help request. 
Some comments:

:: My problem is that Octave first calls the functions and 
:: collects all text for screen output and displays it after all 
:: calculations have been finished.

:There are two possible solutions.  You can turn paging off completely
:by setting the variable page_screen_output to the string "false", or
:you can force the output buffer to be flushed to the pager at any time
:by using the command fflush (stdout).  For an example of this, look at
:the menu function (it's implemented as an M-file).
:Let me know if this isn't what you want, or it doesn't work quite the
:way you expect.

This is exactly what I meant. The simplest solution is to set 
page_screen_output="false".


:: - The function norm(A,"fro") seems to work not correctly in 
::   every case

:Can you send a specific case that fails?

If A is a scalar or vector, octave gives 
error: failed to convert `fro' to a numeric type -- default 
       conversion turned off
In principle this might be correct, since the F-norm of a scalar or 
vector makes no sense. But from the definition of the F-norm 
sqrt(sum(diag(A'*A))) it should work and really does. MATLAB 
reports no error (I guess "fro" is ignored for scalars and vectors).
I think you want to avoid overhead in your functions, but a simple
check of input dimensions could help.

A last question: What is the search hirarchy for commands in octave?
(internal command, octave library m-file, m-file in current directory, ...)

Thank you very much again 

Ludger

-------------------------------------------------------------------------
Dr. Ludger Leushacke
Research Establishment for Applied Science (FGAN)
Research Institute for High Frequency Physics (FHP)
Neuenahrer Str. 20
D-53343 Wachtberg-Werthhoven, Germany
phone:  049-228-852-261
e-mail: leus at gaserv dot fhp dot fgan dot de