Questions tagged [machine-precision]

For questions on the use of machine-precision real numbers (also known as floats), the numbers that can be directly manipulated through the underlying numerical capabilities of your computer system.

15 questions with no upvoted or accepted answers
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Small positive machine number calculation in Mathematica 11.3

In Mathematica version < 11.3, any positive Machine‐Precision Numbers exceeding the range [$MinMachineNumber,$MaxMachineNumber...
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199 views

Classification problem using SVM methods

I am running SVM on mathematica and I a used this code with classes: ...
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99 views

Is it possible to get the original number from DecimalForm?

I'm trying to implement an efficient TSV exporter based on the code from this answer. It works sufficiently quickly but the problem is that OutputForm shows about 6 ...
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0answers
141 views

Enforcing WorkingPrecision in NIntegrate

I have a very complicated 2D integral that I need to calculate repeatedly, and I'm trying to speed it up a bit, since at the moment it's taking a couple of days to complete. One thing I've noticed is ...
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2k views

Set Global Maximum Precision

I'm sure this has been asked before, but I've looked around and can't figure it out: How do I set a global maximum precision for a notebook (or in general, globally)? I have a large notebook in ...
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1answer
52 views

Number definition and approximation

I run these lines: a = 0.833 SetPrecision[a, 20] and this is the output: 0.833 0.83299999999999996270 I expected to ...
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0answers
131 views

Machine Learning Predict Precision

I have this code p = Predict[{1 -> 123456789123456789, 3 -> 987654321987654321}] values are big, more than 15 digits (standard machine precision). when I ...
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0answers
179 views

Printing Precision of Machine Numbers

Is Mathematica making the print precision rounding judgment more stringent based on whether or not the number is above or below the rounding target? If so, why? In my real case, I have many numbers ...
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176 views

Treating a bad conditioned covariance matrix

I am trying to detect outliers in a big dataset using the Mahalanobys distance method. To calculate the Mahalanobys distance for a given vector $x$ from a mean vector $\mu$ you have to compute the ...
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0answers
65 views

Which operations preserve digit precision?

Imagine I had to use numbers with a 600 precision digits. Do all mathematical operations, like +,-,...
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32 views

Contradictions in PositiveDefiniteQ, Det and Inverse in Mathematica

A few words before the working example. Below we find 2 functions which should theoretically transform any matrix to its closest Symmetric Positive Definite (SPD) matrix: ...
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0answers
112 views

Plot a function with very small values, close to zero

I want to plot a function with very small values, close to zero, but even though the limit is -3/2 as x->0, I can't get any ...
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62 views

Getting max precision limit overflow for a very simple calculation

I've never seen this error on such a simple calculation. Does anybody know how to fix this annoying error?
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59 views

ListLinePlot gives the correct values but N doesn't

I have solved a set of 6 differential equations with DSolve. When I use the table command and produce the results of one of the equations given by DSolve, the ListLinePlot command gives me the correct ...
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39 views

Unpredictable behavior of numerical error

A comparison of float calculation and exact expression for NumberForm[0.3^2 - (3/10)^2, 18] gives an exact zero for $0.3$. However, ...