here is the fileDownload 9619_IDF curves toronto.zip
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I agree I was probably too vague. I know it can be done in excel and have in fact done it there. I was hoping as a new user to Maple that I could use the software to write a simple equation, in this case I=A*T^c for a number of values of A, T and C and then plot the distribution of all the values to generate the IDF curve. Maple hopefully would allow me to change some of the assumptions and to view the changes to the curve.

here I = Rainfall intensity (mm/hr), A  rain fall coeffiecent (given), T is time (hour), and the coeffecient C is a given value

In my case where i know that the existing values for the imputs which in my case for Toronto are

return period (yr)                   A               c                     T(hour - in 10 min increments up to 1 hour)

2                                            21.8          -0.78              .167     .25        .33      .416       .5      .583     .66     .75     .833     .916       1.00               

5                                           32              -0.79              .167     .25        .33      .416       .5      .583     .66     .75     .833     .916       1.00 

10                                         38.7          -0.8                .167     .25        .33      .416       .5      .583     .66     .75     .833     .916       1.00 

25                                         45.2          -0.8                .167     .25        .33      .416       .5      .583     .66     .75     .833     .916       1.00 

50                                        53.5           -0.8                .167     .25        .33      .416       .5      .583     .66     .75     .833     .916       1.00 

100                                     59.7            -0.8               .167     .25        .33      .416       .5      .583     .66     .75     .833     .916       1.00 

So my question as clearly as iI can state it is it possible to write an equation in Maple    I=A*T^c    which then uses the A, T and ^c for each return period (2, 5, 10, 25, 50, and 100 year storms) for each 10 minute increment and generates  the points which I can plot. so far all I can do in maple is write one equation at a time for each set of imputs (I Idid this in excel the hard way by writing a formula for each cell and then calculated the result but it is difficult to dynamically change)      If this works successfully I would have a plot with the Y axis being mm/hr (the I value) plotted against the X axis (the 10 min increments in decimal hours) with the corresponding points forming the IDF curves  one for each storm return period (11 points in each curve) 6 curves in all......whew i hope I am clearer