Trying to get dynamic output in console

ruby-talk
1

Hello,
I have a little script that processes excel file and I would like the
script to output some sort of status either line or percent number as it
runs.
How can I output something to console always in the same spot, meaning
that I don't want start new line every time the script advances.
Something like this:
Progress: 51% - I want this number to change and stay in the same spot.

···

--
Posted via http://www.ruby-forum.com/.

2

Perhaps the following example will help you. Please note the \r at the beginning of the format strings.

<code>
0.step(100, 10) do |i|
    printf((i < 100 ? "\rProgress: %02d\%" : "\rProgress: %3d\%"), i)
    $stdout.flush
    sleep(1)
end
puts
</code>

Regards, Morton

···

On Jul 9, 2007, at 1:28 PM, Michal Sza wrote:

Hello,
I have a little script that processes excel file and I would like the
script to output some sort of status either line or percent number as it
runs.
How can I output something to console always in the same spot, meaning
that I don't want start new line every time the script advances.
Something like this:
Progress: 51% - I want this number to change and stay in the same spot.

3

"Michal Sza" <nicpon@nicpon.net> wrote in message
news:033840e271b07d6344e95506465cb536@ruby-forum.com...

Hello,
I have a little script that processes excel file and I would like the
script to output some sort of status either line or percent number as it
runs.
How can I output something to console always in the same spot, meaning
that I don't want start new line every time the script advances.
Something like this:
Progress: 51% - I want this number to change and stay in the same spot.

for i in 1..10 do

print "Progress #{i}% is done.\r"
sleep 1

end

4

This is exactly what I was looking for.
Thanks.

···

--
Posted via http://www.ruby-forum.com/.

5

Hi,

At Tue, 10 Jul 2007 03:21:07 +0900,
Morton Goldberg wrote in [ruby-talk:258465]:

0.step(100, 10) do |i|

      printf("\rProgress: %3.2d%%", i)

    $stdout.flush
    sleep(1)
end
puts

The backslash before % is meaningless and just ignored. You
need two %'s to print one %.

···

--
Nobu Nakada

6

You are of course right: the backslash before the percent should be another percent. But in this case doubling the percent also turns out to be unnecessary. The following works (in Ruby 1.8.2) although one would think that it wouldn't:

<code>
0.step(100, 10) do |i|
    printf((i < 100 ? "\rProgress: %02d%" : "\rProgress: %3d%"), i)
    $stdout.flush
    sleep(1)
end
puts
</code>

It seems to work because the single percent occurs at the end of the format string. Is this a minor bug in printf? Is it behavior inherited from C?

Regards, Morton

···

On Jul 10, 2007, at 12:45 AM, Nobuyoshi Nakada wrote:

Hi,

At Tue, 10 Jul 2007 03:21:07 +0900,
Morton Goldberg wrote in [ruby-talk:258465]:

0.step(100, 10) do |i|

      printf("\rProgress: %3.2d%%", i)

    $stdout.flush
    sleep(1)
end
puts

The backslash before % is meaningless and just ignored. You
need two %'s to print one %.