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m_goldberg
m_goldberg
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Suppose I have a few lists of numbers and want to exponentiate element-wise, then sum up everything into a polynomial.

For example, if I have

a = {1,2,3}
b = {2,4,6}
c = {3,2,1}

I would like to get

poly = xy^2z^3 + x^2y^4z^6 + x^3y^2z

Unfortunately, I am not too familiar with the functional programming style Mathematica is intended to be used for, and I can only write something like

For[i = 1, i < Length[a] + 1, i++,
 term = x^Part[a, i]*y^Part[b, i]*z^Part[c, i];
poly = poly + term;]

As you may expect, this is taking quite a long time to evaluate. Would anybody have any thoughts as to how I would rewrite this to make it more efficient? Thanks in advance.

Suppose I have a few lists of numbers and want to exponentiate element-wise, then sum up everything into a polynomial.

For example, if I have

a = {1,2,3}
b = {2,4,6}
c = {3,2,1}

I would like to get

poly = xy^2z^3 + x^2y^4z^6 + x^3y^2z

Unfortunately, I am not too familiar with the functional programming style Mathematica is intended to be used for, and I can only write something like

For[i = 1, i < Length[a] + 1, i++,
 term = x^Part[a, i]*y^Part[b, i]*z^Part[c, i];
poly = poly + term;]

As you may expect, this is taking quite a long time to evaluate. Would anybody have any thoughts as to how I would rewrite this to make it more efficient? Thanks in advance.

Suppose I have a few lists of numbers and want to exponentiate element-wise, then sum up everything into a polynomial.

For example, if I have

a = {1,2,3}
b = {2,4,6}
c = {3,2,1}

I would like to get

poly = xy^2z^3 + x^2y^4z^6 + x^3y^2z

Unfortunately, I am not too familiar with the functional programming style Mathematica is intended to be used for, and I can only write something like

For[i = 1, i < Length[a] + 1, i++,
 term = x^Part[a, i]*y^Part[b, i]*z^Part[c, i];
poly = poly + term;]

As you may expect, this is taking quite a long time to evaluate. Would anybody have any thoughts as to how I would rewrite this to make it more efficient?

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user5392
user5392
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How to write this without For loop

Suppose I have a few lists of numbers and want to exponentiate element-wise, then sum up everything into a polynomial.

For example, if I have

a = {1,2,3}
b = {2,4,6}
c = {3,2,1}

I would like to get

poly = xy^2z^3 + x^2y^4z^6 + x^3y^2z

Unfortunately, I am not too familiar with the functional programming style Mathematica is intended to be used for, and I can only write something like

For[i = 1, i < Length[a] + 1, i++,
 term = x^Part[a, i]*y^Part[b, i]*z^Part[c, i];
poly = poly + term;]

As you may expect, this is taking quite a long time to evaluate. Would anybody have any thoughts as to how I would rewrite this to make it more efficient? Thanks in advance.