Dataflow Diagrams

[jbennet]

Can someone who knows please explain to me the general idea of Level 0 and Level 1 DFD's?

I dont get it?

[hbk619]

and example level 1 dfd http://www.dcs.bbk.ac.uk/~steve/2_2/sld002.htm

attached is a help sheet i got from college one them.

Pretty much level 1 and 0 are how deep you go, level 1 is detailed 0 not so much. I think.

The level 1 diagram shows the main functional areas of the system under investigation. As with the context diagram, any system under investigation should be represented by only one level 1 diagram.

There is no formula that can be applied in deciding what is, and what is not, a level 1 process. Level 1 processes should describe only the main functional areas of the system, and you should avoid the temptation of including lower level processes on this diagram. As a general rule no business process diagram should contain more than 12 process boxes.

http://www.getahead-direct.com/gwbadfd.htm

if those help?

[jbennet]

Thanks. I asked my computing teacher a bit and he said you dont show the datastores in LV0s apparently

Its for my A2 Computing coursework so ill go along to workshop and ask.

You do computing?

[hbk619]

Best to ask a teacher lol, yup I do BTEC National ICT. tis good, we did that sorta for the Systems Analysis and Design unit.

[jbennet]

"Serunson" does BTEC too i think

[hbk619]

Yar, but I do the one above that hehe, he does the one thats equal to 2 alevels i think. Me get three from mine :)

[jbennet]

ah i see, yeah he must do because he does electronics and physics too