Re: Slowness in function 'open'

[Daniel J Sebald]

Daniel J Sebald wrote:

> 2)  Open the existing file in binary format first and scan--in binary 
> mode--for the number of new-line characters go get the M dimension.  
> Then close/open the file in text mode and scan the first row for N.  
> Rewind, and knowing M x N, off we go.  Just run the existing algorithm.  
> I would think the first binary pass would be very quick.

This one is basically "word count", isn't it.  I tried the following:

A = rand(1000,1000);
save -ascii test.m A
tic, load test.m; toc

Elapsed time is 15.198189 seconds.

Then

address@hidden ~]$ wc -l test.m
1000 test.m

comes back immediately.  That would be a savings if Octave currently has two 
identical passes.  Factor of almost 2, perhaps?  Saving to memory isn't the 
slow part, so I'll guess factory of 1.85 to 1.9.

Dan