Collect: order of terms

[Thomas Ligon]

In this task, I am analyzing partial sums of power series. At one place, I call

exp = collect(expand(exp), m, factor)

The expression exp is a partial sum of a power series in powers of m. After this call, I have one more manipulation and then I print the results.

For the printout, I would like to see the power series in ascending powers of m

1-2m/3+7m**2/18

but collect returns descending powers

7m**2/18-2m/3+1

I was hoping I could call collect and pass a parameter for the order of the output, but didn't find anything.

Does anyone have a recommendation?

[Chris Smith]

perhaps this SO page will help: https://stackoverflow.com/questions/36314035/force-sympy-to-keep-the-order-of-terms

[Thomas Ligon]

Thanks for the tip.