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Old   December 23, 2010, 17:43
Default derivative of scalar
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lig
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Gloria
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Hi, All,

Merry Christmas and Happy New Year!

Please help me to get the expression of derivative of scalar d\Phi /dx.

Thanks

lig
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Old   December 24, 2010, 09:53
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Michael Woopen
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You mean in terms of numerical means? Ever heard of finite differences?

Like: f'(x)=(f(x+h)-f(x))/h

or central: f'(x)=(f(x+h)-f(x-h))/2h
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Old   December 25, 2010, 15:06
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Thank you akOOma. Seems there is no direct code for the derivative of scalar. I will use this basic method. Happy New Year!
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Old   December 26, 2010, 04:02
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If you kow the analytical form of the function you may give an exact derivative. Otherwise you have to use numerical approximations.
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