Q:

Tree-graph visualisation. Convert table to a graph

I need a software, which will allow me to convert a table with tree-like dependences between objects to a picture.  
For example table like this:
object dependsOn
B      A
C      A
D      B
E      B
F      G

Should be converted to a trees like this: 
A - B - D
  \   \ 
    C  E
G - F

The table contains about 500 rows.
I would prefer online site, or mac software.

A:

This is a very specific request and I think that it is unlikely that you will find some s/w that does that, just as you want it, without any effort on your part.
Therefor, I will offer as suggestion that requires you to put in a little work.
Probably the single most widely used tool for visualizing data is GraphViz.
It lets you generate a diagram like this

from descriptive text like this
digraph G {

    subgraph cluster_0 {
        style=filled;
        color=lightgrey;
        node [style=filled,color=white];
        a0 -> a1 -> a2 -> a3;
        label = "process #1";
    }

    subgraph cluster_1 {
        node [style=filled];
        b0 -> b1 -> b2 -> b3;
        label = "process #2";
        color=blue
    }
    start -> a0;
    start -> b0;
    a1 -> b3;
    b2 -> a3;
    a3 -> a0;
    a3 -> end;
    b3 -> end;

    start [shape=Mdiamond];
    end [shape=Msquare];
}

It can be extremely more powerful than that, but I chose the simplest example in the gallery.
What I am getting is that with a few global edits, you could quickly manually create the necessary input. 
And, if you are a programmer, it would be extremely simple to automate the process.
Sorry that it's not an exact match, but its what I always use when face with this sort of thing.  HTH

