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Propagation of uncertainty

Is there any simple method in sage to do a calculation with uncertainties? Something like this: 10±23±1=30±18. Or with a more sophisticated formula: 30±11.67(10×3×(2/10)2+(1/3)2=11.67). Both ways are taken from here, but the second way is also described on wikipedia.


To do such calculations I have already seen a method using RIF's like the following:

R=RIF(8,12)*RIF(2,4)
R.str(error_digits=2); R.lower(); R.upper(); R.center()

Which outputs:

32.?16
16.0000000000000
48.0000000000000
32.0000000000000

But with as one can see the center result is 32 (16+482) instead of 30 (103). Also I think it is a bit complex, because one has to calculate the upper an lower limits before, instead of a simple thing like:

uncertain(10,2)

(And as last point, I think result with the question mark is not very nice)

PS: If one of my calculations is fundamentally wrong please let me know, because I am new to error calculations.

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No.2 Revision

Propagation of uncertainty

Is there any simple method in sage to do a calculation with uncertainties? Something like this: $10\pm2 $(10\pm2) * 3\pm1 (3\pm1) = 30\pm18$. (30\pm18)$. Or with a more sophisticated formula: $30\pm11.67\quad(10 (30±11.67) because of $(10 \times 3 \times \sqrt{(2/10)^2 + (1/3)^2} = 11.67)$. Both ways are taken from here, but the second way is also described on wikipedia.


To do such calculations I have already seen a method using RIF's like the following:

R=RIF(8,12)*RIF(2,4)
R.str(error_digits=2); R.lower(); R.upper(); R.center()

Which outputs:

32.?16
16.0000000000000
48.0000000000000
32.0000000000000

But with as one can see the center result is 32 (16+482) instead of 30 (103). Also I think it is a bit complex, because one has to calculate the upper an lower limits before, instead of a simple thing like:

uncertain(10,2)

(And as last point, I think result with the question mark is not very nice)

PS: If one of my calculations is fundamentally wrong please let me know, because I am new to error calculations.

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No.3 Revision

Propagation of uncertainty

Is there any simple method in sage to do a calculation with uncertainties? Something like this: (10±2)(3±1)=(30±18). Or with a more sophisticated "sophisticated" formula: (30±11.67) because of (10×3×(2/10)2+(1/3)2=11.67). Both ways are taken from here, but the second way is also described on wikipedia.


To do such calculations I have already seen a method using RIF's like the following:

R=RIF(8,12)*RIF(2,4)
R.str(error_digits=2); R.lower(); R.upper(); R.center()

Which outputs:

32.?16
16.0000000000000
48.0000000000000
32.0000000000000

But with as one can see the center result is 32 (16+482) instead of 30 (103). Also I think it is a bit complex, because one has to calculate the upper an lower limits before, instead of a simple thing like:

uncertain(10,2)

(And as last point, I think result with the question mark is not very nice)

PS:


If one of my calculations is fundamentally wrong please let me know, because I am new to error calculations.