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→How do I make Octave use more precision?
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<syntaxhighlight lang="Octave">uint64(18446744073709551610);</syntaxhighlight> | <syntaxhighlight lang="Octave">uint64(18446744073709551610);</syntaxhighlight> | ||
the literal "18446744073709551610" first gets converted to a double precision type, so <code>uint64</code>'s additional precision is lost. Alternatively, the symbolic package, when it works, has a vpa() function for variable-precision arithmetic. Note that arbitrary-precision arithmetic is implemented '''in software''' which makes it much slower than hardware floats. | the literal "18446744073709551610" first gets converted to a double precision type, so <code>uint64</code>'s additional precision is lost. Instead, initialise the <code>uint64</code> with smaller numbers and perform a computation to get the larger number you want. Alternatively, the symbolic package, when it works, has a vpa() function for variable-precision arithmetic. Note that arbitrary-precision arithmetic is implemented '''in software''' which makes it much slower than hardware floats. | ||
At present, however, the symbolic package is almost useless, since even when you get it to compile and not crash, it cannot handle any array type, which hardly helps for an array-oriented language like Octave. If this limitation is not important to you, attempt to use the symbolic package. If you would like to get this fixed, [http://octave.1599824.n4.nabble.com/Internal-Precision-Symbolic-tp4645257p4645594.html Jordi Gutiérrez Hermoso has volunteered] to fix the package for 5000 USD, which can be obtained from a kickstarter compaign. | At present, however, the symbolic package is almost useless, since even when you get it to compile and not crash, it cannot handle any array type, which hardly helps for an array-oriented language like Octave. If this limitation is not important to you, attempt to use the symbolic package. If you would like to get this fixed, [http://octave.1599824.n4.nabble.com/Internal-Precision-Symbolic-tp4645257p4645594.html Jordi Gutiérrez Hermoso has volunteered] to fix the package for 5000 USD, which can be obtained from a kickstarter compaign. | ||