Regex to match unquoted strings but not numbers in CSV - javascript

Trying to write a regex for my text editor (BBEdit) to encode strings that are not already quoted within an almost correctly syntaxed JSON style object so that I can use within a JavaScript context that would otherwise see these text strings as undefined variables.
Thus :
[ 0, 0, Header, 1, 17, 480 ],
[ 1, 0, Start_track ],
[ 1, 0, Title_t, "Dance of the knights (Romeo & Juliet)" ],
[ 1, 0, Tempo, 600000 ],
[ 1, 0, Time_signature, 4, 2, 24, 8 ],
[ 1, 0, Key_signature, 1, "major" ]
would become:
[ 0, 0, "Header", 1, 17, 480 ],
[ 1, 0, "Start_track" ],
[ 1, 0, "Title_t", "Dance of the knights (Romeo & Juliet)" ],
[ 1, 0, "Tempo", 600000 ],
[ 1, 0, "Time_signature", 4, 2, 24, 8 ],
[ 1, 0, "Key_signature", 1, "major" ]


You could use the below regex.
([\[,]\s*)([A-Za-z_]\S*)(?=,|\s*\])
And then replace the match with $1"$2"
DEMO
Example:
> var s = '[ 1, 0, Title_t, "Dance of the knights (Romeo & Juliet)" ],';
> s.replace(/([\[,]\s*)([A-Za-z_]\S*)(?=,|\s*\])/g, '$1"$2"')
'[ 1, 0, "Title_t", "Dance of the knights (Romeo & Juliet)" ],'

Related

How to insert serial numbers for every object in JavaScript

I am trying to make a javaScript game of housie/bingo game. I used the library npm tambola-generator which returns auto generated tickets.
The server side process generates an array similar to this one ...
[{
"_entries": [[0,17,0,0,41,53,0,78,86], [4,0,0,35,0,58,67,80,0]/*, [ ... ] */],
}, {
"_entries": [[0,16,23,0,41,51,0,0,88], [2,20,0,31,43,56,0,0,0]/*, [ ... ] */],
}, {
"_entries": [[0,0,23,33,0,51,0,73,87], [1,0,0,35,42,58,68,0,0]/*, [ ... ] */],
}, {
// ... more items like that ...
}]
I want each ticket to feature a serial number which should be equal to a ticket items's array index but starting with the base of 1 instead of 0.
How does one include such a ticket number so that I can manage tickets for players?
I am just a beginner I couldn't solve it out. The target structure of the above example code should look like the following one ...
[{
"ticketNum": 1,
"_entries": [[0,17,0,0,41,53,0,78,86], [4,0,0,35,0,58,67,80,0]/*, [ ... ] */],
}, {
"ticketNum": 2,
"_entries": [[0,16,23,0,41,51,0,0,88], [2,20,0,31,43,56,0,0,0]/*, [ ... ] */],
}, {
"ticketNum": 3,
"_entries": [[0,0,23,33,0,51,0,73,87], [1,0,0,35,42,58,68,0,0]/*, [ ... ] */],
}, {
// ... more items like that ...
}]

Just use Array.prototype.map for achieving this task.
const entries = [{
"_entries": [
[0, 17, 0, 0, 41, 53, 0, 78, 86],
[4, 0, 0, 35, 0, 58, 67, 80, 0]
],
}, {
"_entries": [
[0, 16, 23, 0, 41, 51, 0, 0, 88],
[2, 20, 0, 31, 43, 56, 0, 0, 0]
],
}, {
"_entries": [
[0, 0, 23, 33, 0, 51, 0, 73, 87],
[1, 0, 0, 35, 42, 58, 68, 0, 0]
],
}];
const tcktEntries = entries.map((entry, index) => {
return {
ticketNum: index + 1,
...entry
};
});
console.log({
tcktEntries
});
.as-console-wrapper {
min-height: 100%!important;
top: 0;
}

Flatten array to 1 line

Hey I need some help here in javascript
[ [ 0, 0, 0, -8.5, 28, 8.5 ],
[ 1, 1, -3, 0, 3, 12 ],
[ 2, 2, -0.5, 0, 0.5, 5.333333333333333 ] ]
I want that array above to be in the form of this
0 0 0 -8.5 28 8.5, 1 1 -3 0 3 12, 2 2 -0.5 0 0.5 5.333333333333333
concat and reduce is placing a comma after each value

You can do it simply using Array.prototype.map() & Array.prototype.join()
Example:
var myArr = [ [ 0, 0, 0, -8.5, 28, 8.5 ],
[ 1, 1, -3, 0, 3, 12 ],
[ 2, 2, -0.5, 0, 0.5, 5.333333333333333 ] ];
var str = myArr.map(insideArr => insideArr.join(" ")).join();
console.log(str);

arr.map(item => item.join(' ')).join(',');

This question can be answered in 2 steps. First, flatten out the array using the Array.prototype.reduce() higher order function with the spread operator (...). Then, use the Array.prototype.join() method to convert the flattened array into a list of numbers.
const arr = [ [ 0, 0, 0, -8.5, 28, 8.5 ],
[ 1, 1, -3, 0, 3, 12 ],
[ 2, 2, -0.5, 0, 0.5, 5.333333333333333 ] ];
const flatten = arr.reduce((combine, item) => [...combine, ...item], [])
.join(' ');

Weird Behaviour when nesting 2D arrays in a 3D array

Currently I'm working on a Minimax algorithm for four-in-a-row in javascript. I have decided to store possible moves in a array, continuing to nest arrays within arrays for every branch.
However, when I attempt to edit a certain value in an array, it edits all other values within the same column.
Code:
var BOARD = [
[0, 0, 0],
[0, 0, 0],
[0, 0, 0]
];
// Put 3 x 2D Arrays into one 3D Array
var NODE_TREE = [BOARD, BOARD, BOARD];
NODE_TREE[1][2][0] = 2;
console.log(NODE_TREE);
Chrome V8 interpreter output:
[ [ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 2, 0, 0 ] ],
[ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 2, 0, 0 ] ],
[ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 2, 0, 0 ] ] ]
What should happen but dosen't:
[ [ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 0, 0, 0 ] ],
[ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 2, 0, 0 ] ],
[ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 0, 0, 0 ] ] ]
Javascript seems to ignore the First dimension index number. This issue only happens when I use an existing array nested within an array. If I were to make a 3D array from scratch, this bug does not happen.

For a lazy initalization, you could use a parsed JSON string.
This generates an independent object without references to the original object.
var BOARD = [
[0, 0, 0],
[0, 0, 0],
[0, 0, 0]
],
JSON_BOARD = JSON.stringify(BOARD),
NODE_TREE = [JSON.parse(JSON_BOARD), JSON.parse(JSON_BOARD), JSON.parse(JSON_BOARD)];
NODE_TREE[1][2][0] = 2;
console.log(NODE_TREE);
.as-console-wrapper { max-height: 100% !important; top: 0; }

When you put BOARD 3 times in to the array, you are not "copying" the items in to the new array, you are actually just creating 3 references to the original BOARD array.
Therefore any change made to any one of those references will be reflected in all instances of BOARD.
If you want to create 3 distinct arrays in your 3d array you will need to clone or copy the arrays. You can do this by mapping on the outer array and copy the contents with Array.prototype.slice();
var BOARD = [
[0, 0, 0],
[0, 0, 0],
[0, 0, 0]
];
// function to map and copy arrays with .slice()
function sliceArrays (outerArray){
return outerArray.map((arr)=>{
return arr.slice()
});
}
var NODE_TREE = [sliceArrays(BOARD), sliceArrays(BOARD), sliceArrays(BOARD)];
NODE_TREE[1][2][0] = 2;
console.log(NODE_TREE);
//[ [ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 0, 0, 0 ] ],
// [ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 2, 0, 0 ] ],
// [ [ 0, 0, 0 ], [ 0, 0, 0 ], [ 0, 0, 0 ] ] ]

BufferGeometry offsets and indices

I was just wondering for a while now what exactly "offsets" and "indices / index" are. Offsets are e.g. mentioned in https://github.com/mrdoob/three.js/blob/dev/src/core/BufferGeometry.js and indices were mentioned in IndexedGeometry, however I can't currently find it anymore in the dev tree.
Although indices seem rather obvious and although I could dive into the code to figure out some maybe-correct answer for myself I'd love to hear an "official" statement :)
Thanks!

There are two ways to defining geometries:
Non-Indexed
"vertices": [ 0, 1, 2, 3, 4, 5, 6, 7, 8, ... ],
"normals": [ 0, 1, 2, 3, 4, 5, 6, 7, 8, ... ]
In this mode every triangle position is as defined and you can't reuse data.
triangle 0: [ 0, 1, 2, 3, 4, 5, 6, 7, 8 ]
Indexed
"indices": [ 0, 1, 2, ... ],
"vertices": [ 0, 1, 2, 3, 4, 5, 6, 7, 8, ... ],
"normals": [ 0, 1, 2, 3, 4, 5, 6, 7, 8, ... ]
In this mode, indices define the order of the data. The first triangle is using indices 0, 1, and 2. These indices will be used to fetch the vertices and normals data:
triangle 0: [ 0, 1, 2, 3, 4, 5, 6, 7, 8 ]
The main benefit of indexed is the possibility of reusing data and uploading less data to the GPU:
"indices": [ 0, 0, 0, ... ],
"vertices": [ 0, 1, 2, 3, 4, 5, 6, 7, 8, ... ]
triangle 0: [ 0, 1, 2, 0, 1, 2, 0, 1, 2 ]
As per offsets...
With offsets you can render specific ranges of your geometry. Instead of drawing from triangle 0 to triangle.length, you can draw from triangle 200 to triangle 400.

Understanding the geometry of a truncated Icosahedron, for rendering

I'm trying to render a truncated icosahedron like above with clickable zones using Three.js.
I found the code for a regular icosahedron
var t = ( 1 + Math.sqrt( 5 ) ) / 2;
var vertices = [
[ -1, t, 0 ], [ 1, t, 0 ], [ -1, -t, 0 ], [ 1, -t, 0 ],
[ 0, -1, t ], [ 0, 1, t ], [ 0, -1, -t ], [ 0, 1, -t ],
[ t, 0, -1 ], [ t, 0, 1 ], [ -t, 0, -1 ], [ -t, 0, 1 ]
];
var faces = [
[ 0, 11, 5 ], [ 0, 5, 1 ], [ 0, 1, 7 ], [ 0, 7, 10 ], [ 0, 10, 11 ],
[ 1, 5, 9 ], [ 5, 11, 4 ], [ 11, 10, 2 ], [ 10, 7, 6 ], [ 7, 1, 8 ],
[ 3, 9, 4 ], [ 3, 4, 2 ], [ 3, 2, 6 ], [ 3, 6, 8 ], [ 3, 8, 9 ],
[ 4, 9, 5 ], [ 2, 4, 11 ], [ 6, 2, 10 ], [ 8, 6, 7 ], [ 9, 8, 1 ]
];
THREE.PolyhedronGeometry.call( this, vertices, faces, radius, detail );
And drew the conclusion that t is φ & vertices consists of all the permutations of:
(0, ±1, ±φ) (±1, ±φ, 0) (±φ, 0, ±1) - From Here
So I modified my vertices as per:
(0, ±1, ±3φ) (±2, ±(1+2φ), ±φ) (±1, ±(2+φ), ±2φ) - From Here
Resulting in:
var vertices = [
[-2, (1+2*t,t], [2,(1+2*t), t ], [-2,-(1+2*t),-t], [2,-(1+2*t),-t ],
[0,-1,3*t], [0,1,3*t], [0,-1,-3*t], [0,1,-3*t],
[1,-(2+t),-2*t ],[1,(2+t),2*t],[-1,-(2+t),-2*t],[-1,(2+t),2*t]
];
Now I understand I have to modify the faces as well. Icosahedron seems to have 20 triangular faces & I can construct any polygon in Three.js with triangles, only.
Does it then follow, that I need the coordinates for 5 pentagons & 12 hexagons in the form of:
5 * 12 + 6 * 20 = 180 triangles
If so, how should I proceed in generating those coordinates? Or even if I am wrong regarding the whole thing.

The JSModeler framework can generate a lot of solids, including truncated icosahedron, so maybe the source can help you.
You can find the code here if you find for GenerateTruncatedIcosahedron:
https://github.com/kovacsv/JSModeler/blob/master/src/extras/solidgenerator.js
The code creates polygons with five and six vertices, but it is easy to replace them with triangles.

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