Easy Graph

Posted by Stephen Allenberg on February 02, 2002 6:44 AM

I would like to produce a graph of

i=a/(t+b)^c

for various times - t against the results - i.
I wish to plot a series of values of - t against
the result i. I am only able to plot two individual
graphs of t and i each against the number of its
numerical entry.

Thanks

Posted by Chris D on February 03, 2002 4:49 AM

I see what you mean..... a chart isn't necessarily a graph

if you list t values of, say, 1 to 250 in a column, then in the next column, apply the formula to get a value of i you get 250 values of t and i

could you then use your 250 columns on a new sheet against 250 rows, as a 250x250 grid

then in 1:1 you say if the result of i is equal to the value of the row number, put an "x", if not, leave it blank.... basically plotting a point on this i/t 250x250 grid

then conditional format the cell so that if it equals "x" then colour it black.

copy this logic down and along the whole 250x250 grid and in theory you will end up with a graph with black points within it

maybe play around with the widths and heights and %age screen size and it should produce a smooth line graph

I played around with you formula using a=1, b=2 and c=3 and t from 1 to 250 and the results were very small numbers, so I divided the answer into 1 to get a real number rather than a fraction - again the results quickly moved into millions which wouldn't be good on a 250x250 grid

in order to resize, I just divided the largest answer by 250 to get a number to divide all the answers by, resulting in nothing larger than 250

admittedly, it distorts the shape of the resultant graph, but retains it's integrity relatively

Not much help, I suspect, but I had noticed you hadn't received any replies at all so far in your previous postings...

good luck !
Chris