Rhumb line modules #728
Rhumb line modules #728
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…n (requires rhumb-distance)
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@DenisCarriere I don't understand why the tests fail, on my computer everything passes... 😞 |
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This is the error, I'll have a look at it. |
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| { | |||
| "name": "@turf/destination", | |||
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@stebogit Here's your problem 🤦♂️ You've named it @turf/destination and when lerna boostrap creates the symbolic links it overwrites the "real" @turf/destination with the rhumb module. I'll fix this and the tests should pass.
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| { | |||
| "name": "@turf/destination", | |||
| "version": "4.3.0", | |||
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For new modules, define them as 4.0.0 (base number of major release) because whenever I publish with Lerna it will automatically bump up the appropriate version (using the same version number as the next release will cause a version conflict with Lerna).
packages/turf-rhumb-bearing/index.js
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| // https://en.wikipedia.org/wiki/Rhumb_line | |||
| // http://www.movable-type.co.uk/scripts/latlong.html#rhumblines | |||
| var getCoords = require('@turf/invariant').getCoords; | |||
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Since you're only dealing with points you can use getCoord which has some extra point validation built-in.
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I haven't understood the difference between the two yet... Maybe some additional explanation on the doc would help?
I'll use getCoord anyway 👍
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Yes more documentation is always better 👍
The Gist is getCoord if you want to retrieve a Point Array (with point validation), getCoords for the entire coordinates as an Array (limited validation).
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Why then not renaming them getCoords and getCoordsArray (I guess this would be suitable for LineString, Polygon, etc. right?); I believe that would make it more clear and intuitive.
packages/turf-rhumb-bearing/index.js
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| * | ||
| * @name rhumbBearing | ||
| * @param {Feature<Point>} start starting Point | ||
| * @param {Feature<Point>} end ending Point |
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Might be worth adding Geometry Object & Array<number> as valid input (input type supported when using getCoord()).
* @param {Geometry|Feature<Point>|Array<number>} start starting Point| * origin Point with the (constant) given bearing. | ||
| * | ||
| * @name rhumbDestination | ||
| * @param {Point|Array<number>} origin starting point |
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Same JSDocs as above Geometry|Feature<Point>|Array<number>
| * } | ||
| * }; | ||
| * var distance = 50; | ||
| * var bearing = 90;// function (from, distance, bearing, units) { |
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// function (from, distance, bearing, units) { ?
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| units = units || 'kilometers'; | ||
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| var distanceInMeters; |
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Might be worth having distanceInMeters as a method in @turf/helpers
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👍 I was thinking about it; maybe distanceInKm (just * 1000 to have meters) as that is Turf's default in many cases?
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Yes many libraries use meters as the unit of measurement.
I solved this using:
var distanceInMeters = radiansToDistance(distanceToRadians(distance, units), 'meters');Might be worth having a method that wraps this behavior. Doesn't have to be to Meters it can be to any distance unit type.
convertDistance(1000, 'miles', 'meters')I dunno about the method name, but something like that.
| if (!origin) throw new Error('origin is required'); | ||
| if (distance === undefined || distance === null) throw new Error('distance is required'); | ||
| if (bearing === undefined || bearing === null) throw new Error('bearing is required'); | ||
| if (!(distance >= 0)) throw new Error('distance must be greater than 0'); |
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Changed this if statement from (distance < 0). If your input is text, then the result would be false since text cannot be less than 0.
> -4 < 0
true
> 5 < 0
false
> 'miles' < 0
false|
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| units = units || 'kilometers'; | ||
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| var distanceInMeters; |
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This entire switch statement can be replaced with only:
var distanceInMeters = radiansToDistance(distanceToRadians(distance, units), 'meters');There was a problem hiding this comment.
very simple and elegant! 👍 👍
| if (process.env.REGEN) write.sync(directories.out + name +'.json', result); | ||
| t.deepEqual(load.sync(directories.out + name + '.json'), result, name); | ||
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| // TODO adopt the following graphical output once rhumbDestination is published |
packages/turf-rhumb-distance/test.js
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| t.deepEqual(distances, load.sync(directories.out + name + '.json'), name); | ||
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| // Removed since (point1 = true & point2 = false) | ||
| // t.ok(distances.kilometers < distances.greatCircleDistance, name + ' distance comparison'); |
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@stebogit Can you have a look at this failing test case, I don't know if the GreatCircle distance is always greater than Rhumb Line Distance (I would assume that your test statement is correct, however the output says otherwise)
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The correct test is reverse, as the GreatCircle line is the shortest path:
distances.kilometers < distances.greatCircleDistance
However it still fails now because of the approximation error due to the incorrect earth radius. I ran the corrected test with 6371km radius and it passes for both cases.
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@stebogit Ok I'm done with commits 🤓 Have a glance at it again and give me a 👍 if you're good to merge this, looks good to me! |
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Looks good to me 😃 |
Added
@turf/rhumb-bearing@turf/rhumb-destination@turf/rhumb-distanceSolves #714 and #681
Ref: #684