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sum and product inside a program - Helge Gabert - 03-29-2016 09:52 PM
I got strange results in one of my programs and it appears that sum() and product() don't work correctly, if called inside a program. Example: POLY(n,z) BEGIN LOCAL k; sum(z^k/k^n, 1, 3, 1); END; returns +inf for POLY(2,.1). But in CAS, from the command line, sum(0.1^k/k^2), returns .1026 . . . Similar problem with product inside a program. RE: sum and product inside a program - roadrunner - 03-29-2016 11:57 PM
I could never get sum() to work right inside a program unless I made it a CAS program. This seems to do what you need: #cas POLY(n,z):= BEGIN LOCAL k; sum(z^k/k^n,k,1,3,1); END; #end -road RE: sum and product inside a program - Helge Gabert - 03-30-2016 12:43 AM
Thanks! I'll try that. RE: sum and product inside a program - Bill_McDonough - 05-22-2017 11:04 PM
Per Cyrille: sum is sum(expr, var, reals...)... this program is missing an EXPORT and a k in the sum to work. EXPORT POLY(n,z) BEGIN LOCAL k; sum(z^k/k^n, k, 1, 3, 1); END; RE: sum and product inside a program - Helge Gabert - 05-24-2017 01:53 PM
Yes, thanks for pointing this out - - I noticed that I forgot the index variable k as soon as I started on the CAS version a while back. All is well. |