Display a linear combination: Difference between revisions
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{{draft task}} |
{{draft task}} |
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The purpose of this task is to display a finite [[wp:linear combination|linear combination]] in an infinite vector basis <math>( |
The purpose of this task is to display a finite [[wp:linear combination|linear combination]] in an infinite vector basis <math>(e_1, e_2,\ldots)</math>. |
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Write a function that, when given a finite list of scalars <math>(\alpha^1,\alpha^2,\ldots)</math>, creates a string representing the linear combination <math>\sum_i\alpha^i e_i</math> |
Write a function that, when given a finite list of scalars <math>(\alpha^1,\alpha^2,\ldots)</math>, creates a string representing the linear combination <math>\sum_i\alpha^i e_i</math> |
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Your output must comply to the following rules: |
Your output must comply to the following rules: |
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* you don't show null terms, unless the whole combination is null. For instance while the output "0" is fine, "e( |
* you don't show null terms, unless the whole combination is null. For instance while the output "0" is fine, "e(1) + 0*e(3)" or "0 + e(1)" are wrong. |
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* you don't show scalars when they are equal to one or minus one. For instance the string "1*e(3)" is wrong. |
* you don't show scalars when they are equal to one or minus one. For instance the string "1*e(3)" is wrong. |
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* you don't prefix by '-' if it follows a preceding term. Instead you use subtraction. Thus "e(4) - e(5)" is correct while "e(4) + -e(5)" is wrong. |
* you don't prefix by '-' if it follows a preceding term. Instead you use subtraction. Thus "e(4) - e(5)" is correct while "e(4) + -e(5)" is wrong. |
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