## How to define (and name) the corresponding safe term comparison predicates in ISO Prolog?

iso_dif/2 is much simpler to implement than a comparison: The built-in \= operator is available You now exactly what arguments to provide to\= Definition Based on your comments, the safe comparison means that the order won’t change if variables in both subterms are instanciated. If we name the comparison lt, we have for example: lt(a(X), … Read more

## OpenGL depth sorting

There is no way to sort the triangles in a perfect way. Look at the examples at end of the Transparency Sorting article on opengl.org wiki. @kos: Give a look at Order Independent Transparency with Dual Depth Peeling and Alpha to Coverage.

## Underscore.js Case Insensitive Sorting

The name to sort by can be the field name OR a function, so pass a function that does a lower-case conversion. var sorted = _.sortBy(array, function (i) { return i.name.toLowerCase(); }); should do the trick.

## Sort a Table[] in Lua

A table in Lua is a set of key-value mappings with unique keys. The pairs are stored in arbitrary order and therefore the table is not sorted in any way. What you can do is iterate over the table in some order. The basic pairs gives you no guarantee of the order in which the … Read more

## pandas groupby sort descending order

Do your groupby, and use reset_index() to make it back into a DataFrame. Then sort. grouped = df.groupby(‘mygroups’).sum().reset_index() grouped.sort_values(‘mygroups’, ascending=False)

## What is the shortest way to simply sort an array of structs by (arbitrary) field names?

As of Go 1.8 you can now use sort.Slice to sort a slice: sort.Slice(planets, func(i, j int) bool { return planets[i].Axis < planets[j].Axis }) There is normally no reason to use an array instead of a slice, but in your example you are using an array, so you have to overlay it with a slice … Read more

## SQL Sorting and hyphens

I learned something new, just like you as well I believe the difference is between a “String Sort” vs a “Word Sort” (ignores hyphen) Sample difference between WORD sort and STRING sort http://andrusdevelopment.blogspot.com/2007/10/string-sort-vs-word-sort-in-net.html From Microsoft http://support.microsoft.com/kb/322112 For example, if you are using the SQL collation “SQL_Latin1_General_CP1_CI_AS”, the non-Unicode string ‘a-c’ is less than the string … Read more

## How do I sort an array of structs by multiple values?

I’m not yet proficient in Swift, but the basic idea for a multiple-criteria sort is: let sorted = conditions.sorted { (lhs: Condition, rhs: Condition) -> Bool in if lhs.set == rhs.set { return lhs.someString < rhs.someString } return (lhs.set) < (rhs.set) }

## Why does Rust not implement total ordering via the Ord trait for f64 and f32?

What is your question, precisely? Are you asking whether NaN exists, or whether it can be obtained as the result of accidental or voluntary computations? Yes, it does and it can. The sort of data structure that requires a total order for keys breaks down completely when the provided order is not a total order. … Read more

## Radix Sort for Negative Integers

You can treat the sign as a special kind of digit. You sort the pile on the units, then the tens, etc. and finally on the sign. This does produce a reversed order for the negatives, you then simply reverse the contents of that bucket. It’s how old mechanical card sorters worked.