mathematica [anomaly]
- To: mathgroup at smc.vnet.net
- Subject: [mg30817] mathematica [anomaly]
- From: Ioan Alexandre Romoscanu <romoscanu at imes.mavt.ethz.ch>
- Date: Wed, 19 Sep 2001 00:17:11 -0400 (EDT)
- Organization: Swiss Federal Institute of Technology (ETHZ)
- Sender: owner-wri-mathgroup at wolfram.com
Hi Some of you might find the Mathematica behaviour represented in the linked image surprising if not even worse. I have a function PerturbationShearRate, which depends of various parameters (which are kept constant here), and the position coordinate z. I choose to plot the function PerturbationShearRate with constant parameters but z, i.e. I plot PerturbationShearRate[z] for z between 0.999 and 1.001. The value of parametrs I see this result. In other words, the graph shows that the function PerturbationShearRate gives values around -268. If now I coose to sample some values in the same z range with Table[ ], the same Kernel says the values are around -301. I am quite worried with this all. I do not ask Mathematica to agree with the Physics, but just to agree with itself. It is a matter of fact that Mathematica is contradicting itself in this issue. I considered the option that the function is very oscillatory. However, changing the sampling in "Table" shoudl give oscillatory results. Any clue? Thanks in advance I. Romoscanu -- _________________________________________ ioan alexandre romoscanu - institut für mechanik CLA G31, eth zentrum, 8092 zürich, schweiz tel. +41 1 632 77 54, +41 76 323 63 05 fax.+41 1 632 11 45, romoscanu at imes.mavt.ethz.ch temporarily nestlé research center H 212 vers-chez-les-blanc 1000 lausanne 26 tel. +41 21 785 83 65 fax. +41 21 785 85 53 _________________________________________