derivatives in cylindrical coords??
- To: mathgroup at smc.vnet.net
- Subject: [mg51260] derivatives in cylindrical coords??
- From: "news" <anonym at bamboo.com>
- Date: Sun, 10 Oct 2004 05:52:34 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
are derivative rules different for cylindrical coordinates?? for example,
taking derivative of unit vectors in Cartesian coords with base units vector
{x, y, z} gives:
d/dx {x, 0, 0} = {1, 0, 0}
d/dy {0, y, 0} = {0, 1, 0}
d/dz {0, 0, z} = {0, 0, 1}
now, for cylindrical coords where base vectors are: {r, phi, z}, does this
hold??
d/dr {r, 0, 0} = {1, 0, 0}
d/dphi {0, phi, 0} = {0, 1, 0}
d/dz {0, 0, z} = {0, 0, 1}
I'm finding that it doesn't work , becuase if you cross d/dr with d/dphi in
cylindrical coords, you get {0,0,0}, and you should get {0,0,1}, so
something is missing in this derivative process, no??? Can anyone help??