Wei Feng

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17 years, 16 days

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These are replies submitted by Wei Feng

As you can see, mfx is a function of x, y and ufx. x and y are just single variables, but ufx is actually a vector of variables. Is the definition I gave above correct? What I am not very sure about is that I gave ufx in the argument list but refered to ufx[k] in the function expression.

As you can see, mfx is a function of x, y and ufx. x and y are just single variables, but ufx is actually a vector of variables. Is the definition I gave above correct? What I am not very sure about is that I gave ufx in the argument list but refered to ufx[k] in the function expression.

It does not solve my problem because I have to use the function mfx with different input arguments later. For example, I can define the alias as "alias(mfx(x)=mFX(x))". But later I need to do "mfx(t[k])". "alias" won't work in that case.

 

It does not solve my problem because I have to use the function mfx with different input arguments later. For example, I can define the alias as "alias(mfx(x)=mFX(x))". But later I need to do "mfx(t[k])". "alias" won't work in that case.

 

This definitely solved my main problem. Now I can compute higher order gradients of a function symbolically.

However, I am a little frustrated with how maple displays the result. It would expand the variables x and y in the dirivatives of the unknow function, as shown in the attached jpg figure.

 

I did define x as r*cos(theta) and y as r*sin(theta). Is there a way to suppress the display to show just x and y. Or maybe even better, do away with the part "(rcos(theta),rsin(theta)" and just display "D1,1(mx)"?

 

This definitely solved my main problem. Now I can compute higher order gradients of a function symbolically.

However, I am a little frustrated with how maple displays the result. It would expand the variables x and y in the dirivatives of the unknow function, as shown in the attached jpg figure.

 

I did define x as r*cos(theta) and y as r*sin(theta). Is there a way to suppress the display to show just x and y. Or maybe even better, do away with the part "(rcos(theta),rsin(theta)" and just display "D1,1(mx)"?

 

Would you mind explaining why you suggested "declare( (x, y)(r, theta) );" not to be used?

Would you mind explaining why you suggested "declare( (x, y)(r, theta) );" not to be used?

I think my essential question is how to avoid defining a function. I just want maple to know that f is a function of x and y, and subsequently x and y are functions of r and theta. You can call them coordinates or whatever.

I read the help document for assume and it did not look like appropriate for my purpose.

I think my essential question is how to avoid defining a function. I just want maple to know that f is a function of x and y, and subsequently x and y are functions of r and theta. You can call them coordinates or whatever.

I read the help document for assume and it did not look like appropriate for my purpose.

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