Edit profiles...

[andrea]

Hi,

I was trying to simulate the egress from a two-story building, using Pathfinder.
I need to characterize different types of people: elderly, children, male and female.

When I modified the speed field, in the Edit profiles box, I selected "Std Normal" distribution and I typed:

0.6 m/s in the "Min" field;
1.2 m/s in the "Max" field;
0.9 m/s in the "Avg" field;
0.3 m/s in the "Std. Dev" field;

then, I clicked OK.
However, the "Std. Dev" value recorded by Pathfinder is not 0.3 m/s but 0.9 m/s, that is the "Avg" value.

I have tried many times, (changing box, changing values, etc.), but the problem is the same...

Can you help me?

Many thanks,
andrea

[Charlie Thornton]

Andrea,

I've attached a couple screen shots.  I went into the profile editor, then on the default profile I specified std normal for the speed and entered the parameters you described.  I think we're using a u for average and s for standard deviation when we draw it out.  Am I getting the same result as you?  I'm having a hard time seeing the bug.

- Charlie

[andrea]

Yes, the first time you get the same result as me...but next times, if I click on the "Edit" button (on the "Edit profiles" box), the "Std. Dev" value is not 0.3 but 0.9 (= avg value); after then, I did nothing, but Pathfinder modified the "Std. Dev" value.

In other words, when I type the 4 values (Min, Max, Avg, Std.Dev) and I click OK, Pathfinder define a type of people with my values, but if I want to modify 1 value (max speed), I have to click on "Edit..." button and I type the new max speed value
BUT 
I have to type the Std.Dev value too, otherwise it's change, and it's like avg value.

i.e.

I type

v_max=1.2
v_min=0.6
v_mean=0.9
st_dev=0.1

Pathfinder record:

v_max=1.2
v_min=0.6
v_mean=0.9
st_dev=0.1

After, I want to change the v_max value, then I click on the Edit button and type 1.3 in the v_max field, the I click OK.

Pathfinder record now:

v_max=1.3  (value modified by me)
v_min=0.6
v_mean=0.9
st_dev=0.9 (= v_mean, NOT 0.1)

Every time I want to change a value, I have to remember to re-type the right st_dev value too.......

[Charlie Thornton]

Aha!  I was reviewing the file history for the Profiles panel and found this check-in comment:

Fixed a bug in the profile panel's StdNormDlg that would prefill the standard deviation with the average instead.  This would cause the values to be saved incorrectly if OK was pressed without changing any values.

I quick glance at the code verified that prior to 8/21/2008 we were initializing the standard deviation field with the average.  The 9/9/2008 version that's on the web right now should work better - it's what I was using when I couldn't reproduce the bug.  Check out the mailing list thread for the download link and release notes:

http://www.thunderheadeng.net/forum/index.php/topic,22.0.html

You may notice that in September we suggested a new release in a month - we ended up doing more work on the last PyroSim release than we thought we would and the Pathfinder release got pushed back.  However, we've already got geometry editing and PyroSim model import working and now we're working on some bug fixes and better floor finding (now that imported geometry can be more interesting).

- Charlie

[Charlie Thornton]

The download link in that mailing list post pointed to the wrong release (July 10, 2008).  I've fixed it now - but that would explain a lot.

- Charlie