Errors at discontinuities
- To: mathgroup at smc.vnet.net
- Subject: [mg65110] Errors at discontinuities
- From: "Narasimham" <mathma18 at hotmail.com>
- Date: Wed, 15 Mar 2006 06:28:22 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Errors appear at start / period cross-over points of a triangular wave on t-axis with period a, amplitude b. Why does not Plot[ D[fn[t,3,4],t] / D[fn[t,5,5.65],t] , {t, 0,tmax}] ; Or Plot[ D[fn[t,3,4],t] , {t, 0,tmax}] ; work at beginning when the same works erroneously later on in sl1 and gets self-corrected at sl2? And how to remedy the situation? TIA a= 4 ; b = 3 ; tmax=10; fn[u_,lam_,A_]=A*ArcSin[Sin[ 2 Pi u/lam]]*2/Pi ; Plot[ fn[t,a,b], {t, 0,tmax}] ; Plot[ D[fn[t,a,b],t] / D[fn[t,c,d],t] , {t, 0,tmax}] ; sl1=D[fn[t,a,b],t]/D[fn[t,c,d] ] ; Plot[ sl1 , {t, 0, tmax}] ; sl2= D[fn[t,a,b],t]/D[fn[t,c,d],t] ; Plot [sl2, {t, 0, tmax}] ;