how to simply result from diff result
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Hi,
I used "diff" to differentiat an symbolic expression (which is a 2*1 matrix in terms of one variable "p1" )and I get the result is
if true
% (993145510909945291290970062799168703243609151945831132541235246491728972506726400000*p1^24)/(11*(66209700727329686086064670853277913549573943463055408836082349766115264833781760*p1^25 + 76000450310455048509674258747439313371109099869460786758580060874282689)) - (3441252636555596989920201187800307357046462757955062829318209447303288193024000000*p1^24*(19108119629907347404438264008256005850407040083437790990093366142500865431029415936*p1^25 - 141284835465018257235063952180851629982268381766690721762239555200372318157))/(11*(66209700727329686086064670853277913549573943463055408836082349766115264833781760*p1^25 + 76000450310455048509674258747439313371109099869460786758580060874282689)^2)
(3441252636555596989920201187800307357046462757955062829318209447303288193024000000*p1^24*(63693732099691158014794213360853352834690133611459303300311220475002884770098053120*p1^25 - 43472257854599900738270425141974962844044977607104383496234591147576231557))/(11*(66209700727329686086064670853277913549573943463055408836082349766115264833781760*p1^25 + 76000450310455048509674258747439313371109099869460786758580060874282689)^2) - (3310485036366484304303233542663895677478697173152770441804117488305763241689088000000*p1^24)/(11*(66209700727329686086064670853277913549573943463055408836082349766115264833781760*p1^25 + 76000450310455048509674258747439313371109099869460786758580060874282689)
end
Anyone can tell me how to simplify this result...I have used "simplify" but the result doesn't look better enough
if true
% (51061483509298234744021093266326713799853337869221735203326270028773557256849240290965339520235810633978267214726144573886032503926667005712580319641600000*p1^24)/(66209700727329686086064670853277913549573943463055408836082349766115264833781760*p1^25 + 76000450310455048509674258747439313371109099869460786758580060874282689)^2
-(36472488679003875759150208868231165720314307528440215941247217470038257246649230534343240731249455251103241160127018820611162429237123481071517696000000000*p1^24)/(66209700727329686086064670853277913549573943463055408836082349766115264833781760*p1^25 + 76000450310455048509674258747439313371109099869460786758580060874282689)^2
end
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답변 (1개)
Roger Stafford
2013년 6월 2일
You undoubtedly obtained this kind of baffling result because your original symbolic expression contained numerical values in decimal fraction form. It would be better to use short - preferably single character - symbols for these values before attempting to find the derivative. You can substitute numerical values for these afterward.
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