Search found 112 matches

by nikvyas
Wed Dec 08, 2010 1:08 pm
Forum: Vensim
Topic: POISSON DISTRIBUTION
Replies: 2
Views: 2646

Re: POISSON DISTRIBUTION

Thanks for that Tom - most useful.

And thanks for taking the trouble to add rainbow colours to your toolbar - glad i had a couple of Paracetamol to hand :mrgreen:
by nikvyas
Tue Dec 07, 2010 11:04 am
Forum: Vensim
Topic: POISSON DISTRIBUTION
Replies: 2
Views: 2646

POISSON DISTRIBUTION

Hello all. I'm having a mental block with implementing a POISSON distribution within Vensim. If the mean is 1.5, then (taken from Excel), the probability of: 1 is 22.3% 2 is 33.4% 3 is 12.5% etc, etc. Now, how do I represent this in Vensim please (obviously the mean will be variable)? The RANDOM POI...
by nikvyas
Fri Feb 05, 2010 11:52 am
Forum: Vensim
Topic: Subscripts and graphs.
Replies: 4
Views: 3117

Thanks Bob.

Wow, was it really that simple? I had always assumed that both the left and the right had to have the same number of subscripts.

Thanks again.
by nikvyas
Fri Feb 05, 2010 9:50 am
Forum: Vensim
Topic: Subscripts and graphs.
Replies: 4
Views: 3117

Actually, of the three subscripts referred to above, the full range is used on one and only the first subscript of each of the other two is used - i.e., - [FEAR, a1, p1]

So if it is possible to reduce it to just the one subscript (FEAR) it would be beneficial.
by nikvyas
Fri Feb 05, 2010 9:08 am
Forum: Vensim
Topic: Subscripts and graphs.
Replies: 4
Views: 3117

Subscripts and graphs.

Good morning all. I have question about subscripts and the resulting ouput graphs. The first question is to do with the number of subscripts on one variable. It's a little difficult to explain, but I'll try anyway! I have a variable (called example1) that uses two subscript ranges (aircraft,probabil...
by nikvyas
Fri Feb 05, 2010 8:44 am
Forum: Vensim
Topic: text outputs
Replies: 8
Views: 3954

Thanks Bob.
by nikvyas
Tue Feb 02, 2010 2:34 pm
Forum: Vensim
Topic: text outputs
Replies: 8
Views: 3954

Thanks jj - I'll found the section in the Reference Guide. It looks like I might have to make myself a strong coffee before I read it!
by nikvyas
Tue Feb 02, 2010 1:35 pm
Forum: Vensim
Topic: text outputs
Replies: 8
Views: 3954

Thanks for your response Bob - much appreciated. Unfortunately it seems as if you've ventured into an advanced subscript topic that I've yet to visit. Could you please explain how LReadiness and EReadiness are defined please? I'm assuming they are some sort of sub-subscript of Readiness? I've tried ...
by nikvyas
Fri Jan 29, 2010 12:06 pm
Forum: Vensim
Topic: text outputs
Replies: 8
Views: 3954

Thanks Bob. I don't know if you guys know what FE@R is (forced elements at readiness), but what it basically shows is the readiness of an aircraft. If an aircraft is immediately ready (for take-off), it is considered to be at "R0". If an aircraft is 24 hours from being ready, it is conside...
by nikvyas
Fri Jan 29, 2010 10:38 am
Forum: Vensim
Topic: text outputs
Replies: 8
Views: 3954

text outputs

Hello. I have a query wrt text outputs. For instance, I have a subscript with 12 elements. If an element is between 0 and 24, I want to display "a". If it's between 24-48, I want to display "b" etc etc. Following this, I want to sum the subscript so that I get the total number of...
by nikvyas
Fri Oct 03, 2008 7:08 am
Forum: Vensim
Topic: ....... is not used in the model
Replies: 6
Views: 4097

Thanks for the offer Bob - been away for a while, so just read your post.

I've sorted the problem out - it turned out that I had made a couple of silly mistakes (mis-named a couple of subscript elements). It seems to be running OK now.
by nikvyas
Tue Sep 09, 2008 1:36 pm
Forum: Vensim
Topic: ....... is not used in the model
Replies: 6
Views: 4097

Thanks Bob and Tony. You are both right - the error message masked the fact that there are other real errors involving the subscripts. I've tried to trace the cause of the error but am unable to do so. Bob - is there a chance you could have a quick look if I were to email you the model? Unfortunatel...
by nikvyas
Tue Sep 09, 2008 9:37 am
Forum: Vensim
Topic: ....... is not used in the model
Replies: 6
Views: 4097

Tony - they do stop me from running the model because I get the message "Model has errors and cannot be simulated" Are you saying that I am going to have to go to every one of the variables that is at the end of a chain and check the supplementary box? Why? I haven't had to do so before .....
by nikvyas
Tue Sep 09, 2008 9:19 am
Forum: Vensim
Topic: ....... is not used in the model
Replies: 6
Views: 4097

....... is not used in the model

Morning/afternoon/evening everyone. I'm getting a particularly annoying error message that is preventing me from running my model. "variable1 is not used in the model" I'm getting this message for every single variable that is at the end of a logic chain. - these variables are used to disp...
by nikvyas
Mon Mar 03, 2008 11:54 am
Forum: Vensim
Topic: Human Resources Model
Replies: 1
Views: 1967

Human Resources Model

Good morning everyone. I would like to add Human Resources to my ever burgeoning model. It's obviously an extremely complex subject and one that requires more knowledge than I have in order to model it. Can somebody recommend where I might be able to download a HR model that requires some "twea...
by nikvyas
Mon Feb 25, 2008 9:09 am
Forum: Vensim
Topic: I don't understand.........................
Replies: 10
Views: 5063

Thanks very, very much Bob.
by nikvyas
Fri Feb 22, 2008 10:03 am
Forum: Vensim
Topic: I don't understand.........................
Replies: 10
Views: 5063

Hi JJ - yes, at the moment I haven't put any feedback loops and on any particular seed the results will be exactly the same on every run. However, one of the purposes of the model is to give a predicted measure if all variables were at their nominal values. We can then run a series of sensitivity an...
by nikvyas
Fri Feb 22, 2008 8:22 am
Forum: Vensim
Topic: I don't understand.........................
Replies: 10
Views: 5063

Thanks Bob. You couldn't elaborate a bit on "there remains one use of RANDOM UNIFORM that has not been replaced by the variable random number. It looks like all the others are clean." could you?

Thanks

Nik
by nikvyas
Thu Feb 21, 2008 8:09 am
Forum: Vensim
Topic: I don't understand.........................
Replies: 10
Views: 5063

Thanks very much for your replies Tony, Kind Soul JJ and Bob. I agree that the model is a little too complex, but believe me when I say that I've tried very hard to reduce the complexity! I'll try to do what you suggest JJ - makes perfect sense. Thanks very much for looking into this Bob. The attach...
by nikvyas
Wed Feb 20, 2008 3:31 pm
Forum: Vensim
Topic: I don't understand.........................
Replies: 10
Views: 5063

I don't understand.........................

Afternoon everyone. I was wondering if some kind soul (Bob, JJ) can help me with the attached model? I can't understand why in the process "Total", the values of [s1,p1], [s1,p2], [s1,p3], [s1,p4] ...................[s1,p20] aren't exactly the same at a particular point in time. For instan...
by nikvyas
Fri Feb 01, 2008 11:06 am
Forum: Vensim
Topic: 2d Subscripting option in Tabletool displays only one elemen
Replies: 6
Views: 3549

Afternoon all

I have another question wrt elements of a subscript. Is there a maximum to the number of elements I can have in a single subscript? For instance, could I have:

test : (t1-t10000) ?

Thanks

Nik
by nikvyas
Thu Jan 17, 2008 7:50 am
Forum: Vensim
Topic: Error Message
Replies: 6
Views: 3028

Thanks Bob.
by nikvyas
Tue Jan 15, 2008 9:13 am
Forum: Vensim
Topic: Error Message
Replies: 6
Views: 3028

Thanks Bob. However, it isn't ideal to leave the model unprotected unfortunately. The model is situated on the company network (it has to be, for various reasons) and there are a number of people who have Vensim on their computers. There is therefore always a danger of somebody opening the model and...
by nikvyas
Mon Jan 14, 2008 11:59 am
Forum: Vensim
Topic: Error Message
Replies: 6
Views: 3028

Hi Bob. Yes using 5.7 (DSS). I've tried using different passwords, but they all result in the same error message. Having thought about it, all the other models that are password protected were created using the previous version. I can open and save all the older models with no error ...................
by nikvyas
Mon Jan 14, 2008 10:45 am
Forum: Vensim
Topic: Error Message
Replies: 6
Views: 3028

Error Message

Good morning all. I get the following error mesage when I try to save a .vmf file that I've just password protected: "PROGRAM ERROR PLEASE CONTACT VENTANA Incomplete/Bad file write - save as text, close Vensim and reopen." However, if I clear away the password, everything is fine. I have a...