Develop Reference

Why is this comparison not working, using google aps scripts?

The code below is not giving me the expected result.
It's to compare rows from two ranges and, although the second range's last row equals the one from the first range, it gives me false as the result.
var entryValuesCom = sheet.getRange(7, 1, LastRowSource, 9).getValues();
var dbDataCom = dbSheet.getRange(2, 1, dbSheet.getLastRow(), 9).getValues();
var entryVlArray = new Array();
var dbArray = new Array();
for (var r = 0; r < entryValuesCom.length; r++) {
if (entryValuesCom[r][0] != '' && entryValuesCom[r][5] != 'Daily Ledger Bal') {
entryVlArray.push(entryValuesCom[r]);
}
}
for (var a = 0; a < dbDataCom.length; a++) {
if (dbDataCom[a][1] != '' && dbDataCom[a][8] == bank) {
dbArray.push(dbDataCom[a]);
}
}
var duplicate = false;
loop1:
for (var x = 0; x < entryVlArray.length; x++) {
loop2:
for (var j = 0; j < dbArray.length; j++) {
if (JSON.stringify(entryVlArray) == JSON.stringify(dbArray)) {
duplicate = true;
break loop1;
}
}
}
Here's a snapshot of how the array is coming:
I've tried it using .join(), but still...
This is for thousands of rows, so is this going to do well performance wise?

I believe your goal as follows.
You want to compare the arrays of entryVlArray and dbArray using Google Apps Script.
When the duplicated rows are existing between entryVlArray and dbArray, you want to output duplicate = true.
Modification points:
When your script is modified, at if (JSON.stringify(entryVlArray) == JSON.stringify(dbArray)) {, all 2 dimensional arrays are compared. I think that this might be the reason of your issue. From your script, I think that it is required to compare each element in the 2 dimensional array.
When above points are reflected to your script, it becomes as follows.
Modified script:
From:
var duplicate = false;
loop1:
for (var x = 0; x < entryVlArray.length; x++) {
loop2:
for (var j = 0; j < dbArray.length; j++) {
if (JSON.stringify(entryVlArray) == JSON.stringify(dbArray)) {
duplicate = true;
break loop1;
}
}
}
To:
var duplicate = false;
for (var x = 0; x < entryVlArray.length; x++) {
for (var j = 0; j < dbArray.length; j++) {
if (JSON.stringify(entryVlArray[x]) == JSON.stringify(dbArray[j])) {
duplicate = true;
break;
}
}
}
console.log(duplicate)
By this modification, when each element (1 dimensional array) in the 2 dimensional array is the same, duplicate becomes true.
Note:
As other method, when an object for searching each row value is prepared, I think that the process cost might be able to be reduced a little. In this case, the script is as follows. Please modify as follows.
From:
var duplicate = false;
loop1:
for (var x = 0; x < entryVlArray.length; x++) {
loop2:
for (var j = 0; j < dbArray.length; j++) {
if (JSON.stringify(entryVlArray) == JSON.stringify(dbArray)) {
duplicate = true;
break loop1;
}
}
}
To:
var obj = entryVlArray.reduce((o, e) => Object.assign(o, {[JSON.stringify(e)]: true}), {});
var duplicate = dbArray.some(e => obj[JSON.stringify(e)]);
References:
reduce()
some()
Added:
About your following 2nd question,
AMAZING!!!! Would there be a way of capturing these duplicates in a pop up, using reduce() and some()?
When you want to retrieve the duplicated rows, how about the following script? In this case, I thought that filter() is useful instead of some().
Modified script:
var obj = entryVlArray.reduce((o, e) => Object.assign(o, {[JSON.stringify(e)]: true}), {});
// var duplicate = dbArray.some(e => obj[JSON.stringify(e)]);
var duplicatedRows = dbArray.filter(e => obj[JSON.stringify(e)]);
console.log(duplicatedRows)
In this modified script, you can see the duplicated rows at the log.
About a pop up you expected, if you want to open a dialog including the duplicated rows, how about adding the following script after the line of var duplicatedRows = dbArray.filter(e => obj[JSON.stringify(e)]);?
Browser.msgBox(JSON.stringify(duplicatedRows));

How to shuffle characters in a vertical inverted pattern?

I have a string "ABCDEFGHIJKLMN" that I need to shuffle in a specific manner. To do that, I write the characters sequentially in columns bottom -> top and then left -> right (4 chars per column for example) until all characters are done. If the last column is not complete, then the empty spaces need to be on the bottom (this is very important). Like so:
D H L N
C G K M
B F J
A E I
The shuffle is accomplished by producing a new string reading the block of letters as we read text, in rows left -> right:
"DHLNCGKMBFJAEI"
The cases where the columns are not complete (word.size % column_height !=0) complicate things considerably.
I came up with a few solutions, but I'm not sure if there is a simpler (ie, shorter OR easier to read) and more elegant way of coding this problem. My solutions either have an ugly, separate block of code to handle the final incomplete column or seem way too complicated.
My question is, could it be done better?
If you don't want any spoilers and decide to try and figure it out for yourself, stop reading now. If you want to work from what I fiddled so far, then a working piece of code is
var result = "";
var str = "ABCDEFGHIJKLMN";
var nr_rows = 4;
var current_row = 4;
var columns = Math.floor(str.length / nr_rows);
var modulus_table = str.length % nr_rows;
var modulus_position = -1;
for (var i = 0; i < nr_rows; i++) {
for (var j = 0; j < columns; j++) {
result += str[current_row + j * nr_rows - 1];
}
if (modulus_table > 0) {
result += str[str.length + modulus_position];
modulus_table--;
modulus_position--;
}
current_row--;
}
console.log(result);
Moving on to arrays, the next example would loop through each character, placing it correctly in a matrix-like array, but it doesn't work. The array needs to be created another way. For another example of this issue, see How to create empty 2d array in javascript?. This would also need an ugly hack to fix the last characters on the last incomplete column aligning to the bottom instead of the top.
var result = [[],[]];
var str = "ABCDEFGHIJKLMN";
var nr_rows = 4;
var row = nr_rows - 1;
var column = 0;
for (var i = 0; i < str.length; i++) {
result[row][column] = str[i];
row--;
if (row < 0) {
row = nr_rows;
column++;
}
}
console.log(result);
This last method goes full matrix array, but it quickly becomes complicated, since it needs to loop through the array in 3 different directions. First, create a dummy array with the characters in the wrong place, but where the 'undefined' positions correspond to those that should be left empty. That is acomplished by populating the array 'rotated 90º' from the reading orientation.
Without this first step, the empty positions would be stacked at the bottom instead of the top.
A second pass is required to re-write the caracters in the correct places, skipping any holes in the matrix using the 'undefined' value. This check is made for every position and there is no separate block of code to handle an incomplete last line.
A third pass then reads every character in order to form the final shuffled string. All this seems way too complicated and confusing.
// matrix populated top->bottom and left->right
// with the characters in the wrong place
// but the undefined postions in the correct place of the empty positions
var matrix = [];
var str = "ABCDEFGHIJKLMN";
var rows = 4;
var columns = Math.ceil(str.length / rows);
var k = 0;
for (var i = 0; i < rows; i++) {
matrix[i] = [];
for (var j = columns - 1; j >= 0; j--) {
matrix[i][j] = str[k];
k++;
}
}
// populate the matrix with the chars in the correct place and the 'undefined' positions left empty
var k = 0;
for (var i = 0; i < rows; i++) {
for (var j = 0; j < columns; j++) {
if (matrix[i][j] != undefined) {
matrix[i][j] = str[k];
k++;
}
}
}
// read matrix in correct direction and send to string, skipping empty positions
var result = "";
for (var j = columns - 1; j >= 0; j--) {
for (var i = 0; i < rows; i++) {
if (matrix[i][j] != undefined) {
result += matrix[i][j];
}
}
}
console.log(result);

What if you just split/reverse the array into column groups, and convert to rows?
const result = str.match(/.{1,4}/g) // split string into groups of 4
.map(i => i.split('').reverse()) // reverse each group (bottom to top, and solves the last col issue)
.reduce((res, col) => { // reduce the groups into rows
col.forEach((c, i) => res[i] += c) // concat each string char to the right row
return res
}, ['','','','']) // initialise empty strings per row
.join('') // join the rows up
Fiddle here

If you wish to return a string, I don't see why any intermediate result should use an array when it doesn't have to. The following could use one less array, but it's convenient to use split and an array to control the while loop rather than mutate the string.
The idea is to fill the strings from the bottom up until the column is full, then keep adding from the bottom of each column until it runs out of characters to assign. The row to start filling from is based on how many characters are left and how many rows there are.
Rather than building strings, it could build arrays but then generating a string requires multiple joins.
It can also produce results where there are insufficient slots for all the characters, so a result using 9 characters from 10 or more using a 3x3 "matrix" (see last example).
function verticalShuffle(s, rows, cols) {
var result = [''];
s = s.split('');
while (s.length && result[0].length < cols) {
for (var i = (rows < s.length? rows : s.length) -1 ; i>=0; i--) {
if (!result[i]) result[i] = '';
result[i] += s.splice(0,1)[0] || '';
}
}
return result.join('');
}
var s = 'ABCDEFGHIJKLMN';
console.log(verticalShuffle(s, 4, 4)); // DHLNCGKMBFJAEI
console.log(verticalShuffle(s, 6, 3)); // FLNEKMDJCIBHAG
// Only use 9 characters
console.log(verticalShuffle(s, 3, 3)); // CFIBEHADG
This uses plain ed3 functionality that will run in any browser. I don't see the point of restricting it to ECMAScript 2015 or later hosts.

If interpret Question correctly, you can use for loop, String.prototype.slice() to to populate arrays with characters of string. Use Array.prototype.pop() within recursive function to get last element of array until each array .length is 0.
To create array
[
["D","H","L","N"],
["C","G","K","M"],
["B","F","J"],
["A","E","I"]
]
from vertically inverted string you can use for loop, String.prototype.slice() to set array of arrays containing elements having .length 4, or 3 once .length of parent array is 2, having been set with two arrays containing four elements
var str = "ABCDEFGHIJKLMN";
function fnVerticalInvert(str, arr, res) {
if (!arr && !res) {
arr = []; res = "";
}
if (str) {
for (var i = 0; i < str.length; i += 4) {
arr.push([].slice.call(str.slice(i, i + 4)));
}
}
for (var i = 0; i < arr.length; i++) {
if (arr[i].length) {
res += arr[i].pop()
}
}
if (arr.some(function(curr) {return curr.length}))
return fnVerticalInvert(null, arr, res);
for (var i = 0, l = 4, j = 0, n = l - 1, k; i < l; i++, j += l) {
if (i === l / 2) k = j;
arr[i] = [].slice.call(res.slice(!k ? j : k, !k ? j + l : k + n));
if (k) k += n;
}
return {str: res, arr:arr};
};
var res = fnVerticalInvert(str);
console.log(res);

Javascript iterate objects in array only after current object

For example:
From
[x0,x1,x2,x3] - x0 compares itself to x1,x2 and x3.
x1 compares itself to x0, x2 and x3. And so on...
To
[x0,x1,x2,x3] - x0 compares itself to x1,x2 and x3.
x1 compares itself to x2 and x3 only.
x2 only compares itself to x3.
x3 does not need to do any comparison at all.
Essentially I'm looking to traverse an array one way only, with every element behind the current element ignored.
for (var i = 0; i < boids.length; i++) {
//boids is an array containing elements "boid"
var d = distSquared(this.position.x, this.position.y, boids[i].position.x, boids[i].position.y);
//get distance between current boid and all other boids in array.
//Looking to change this to get distance between current boid and all other boids infront of this element in the array.
if (boids[i] == this) { //if the boid being compared is to its own self, skip it.
continue;
}
}
How would I go about implementing such a structure?

What you are looking for is something like this:
var a = [1,2,3,4];
for(var i=0; i<a.length; i++){
for(var j=i+1; j<a.length; j++){
console.log(i,j)
}
}

You can use Array.prototype.filter() to exclude an element or elements from an array
var arr = [1,2,3,4,5];
for (var i = 0; i < arr.length; i++) {
var curr = arr[i];
var not = arr.filter(function(_, index) {
return index != i
});
console.log(`curr:${curr}`);
not.forEach(function(el) {
console.log(`${curr} is not ${el}`)
})
}

You might do like this. Shaping up how to compare is up to you.
var arr = [1,2,3,4,5],
result = arr.map((e,i,a) => a.slice(i+1).map(n => e-n));
console.log(result);

I used Array.prototype.indexOf() to solved my issue.
var j = boids.indexOf(this);
//get index of current element i array.
if (j < boids.length) {
// if the index is lower than the overall length of the array (e.g. check traverse the array to elements infront of the current element, ignoring those behind)
//Perform calculations here
j++; //increment j
}

Iterate through an array and concatenate another array all the values before next iteration of first array?

I'm trying to build a list of Urls. The structure is like this:
http://somedomain.com/game_CATEGORY?page=NUMBER.
I have an array of game categories, ranging from action games category to word games category.
I have an array of numbers, 1 through 20.
I have pieces of the url saved as strings.
I've been trying for a day to combine them in this way:
cats = ["action","adventure","arcade","board","card","casino","casual","educational","family","music","puzzle","racing","role_playing","simulation","sports","strategy","trivia","word"],
nums = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20],
urlString1 = "http://example.com/game_",
urlString2 = "?page=",
madeUrl1 = [],
x = 1, // counter for page numbers
madeUrl2 = [];
for (var i = 0; i < cats.length; i++) {
madeUrl1.push(urlString1+cats[i]+urlString2);
};
for (var i = 0; i < madeUrl1.length; i++) {
madeUrl2.push(madeUrl1[i]+x);
x++;
};
console.log(madeUrl2);
This gets me partially there. But its printing out one number per category. I need each category printout to have ALL 20 numbers added, then move on to the next category.

You'd need to nest another for loop inside your second one. Something like:
for (var i = 0; i < madeUrl1.length; i++) {
for (int j = 0; j < nums.length; j++) {
madeUrl2.push(madeUrl1[i]+nums[j]);
}
};
That way you're iterating through the base URLs you prepared in madeUrl1, and then for each of those you're iterating through each number you have in the array.
If the numbers are simply sequential from 1 to 20, you don't even need the nums array:
for (var i = 0; i < madeUrl1.length; i++) {
for (var x = 1; x <= 20; x++) {
madeUrl2.push(madeUrl1[i]+x);
}
};
And the whole thing could be accomplished with a single nested for loop:
for (var i = 0; i < cats.length; i++) {
for (var x = 1; x <= 20; x++) {
madeUrl1.push(urlString1+cats[i]+urlString2+x);
}
};

You can use the code below:
cats = ["action","adventure","arcade","board","card","casino","casual","educational","family","music","puzzle","racing","role_playing","simulation","sports","strategy","trivia","word"],
nums = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20],
urlString1 = "http://example.com/game_",
urlString2 = "?page=",
madeUrl1 = [],
x = 1;
for (var i = 0; i < cats.length; i++) {
for (var j = 0; j < nums.length; j++) {
madeUrl1.push(urlString1+cats[i]+urlString2+nums[j]);
x++;
};
};
console.log(madeUrl1);
What we did here, is first nesting our loops. E.g., it will first loop through the first array, and when it arrives at it first item, in this case a category, it will run the nested loop 20 times, appending each number to the page. After done, it continues to the second category and so on.

How should I represent data for effective searching and comparing strings

I have two array with length 300. They look like this (JSON representation):
[
[
["word1",0.000199],
["word2",0.000102],
...
["word15",0.000102]
],
...
[
["anotherword1",0.0032199],
["anotherword2",0.032302],
...
["anotherword15",0.0320102]
]
]
And I have this bruteforce algorithm:
for(var i = 0; i < 300; i++)
{
for(var j = 0; j < 15; j++)
{
for(var ii = i + 1; ii < 300; ii++)
{
for(var jj = 0; jj < 15; jj++)
{
for(var jjj = 0; jjj < 15; jjj++)
{
if(new_keywords[i][j][0] === new_keywords[ii][jj][0] && new_keywords[ii][jj][0] === state_keywords[i][jjj][0])
{
console.log(0);
}
}
}
}
}
}
I need to search for same words in those arrays and if words are the same, then I sum values and divide sum by 3 and replace that value in state_keywords array. So for each word which is more then once in array I have means of its values.
Now... my approach is very bad because I have now about 300 mil iterations and that is crazy. I need some better implementation of my array in JavaScript. Something like lexikographical tree or kd-tree or something.
Thank you.
EDIT:
Here is http://jsfiddle.net/dD7yB/1/ with example.
EDIT2:
I'm sorry if I'm not clear enough. So what exaclty I'm doing:
I have array state_keywords. Indexes are from 0 to 299 and they representing a themes...
Each theme may be represented by 15 words and every time new_keywords array arrives, they may be different.
When new_keywords array arrive I need to check every word in that array if it is in state_keywords array on same theme index.
If it is: add probabilities up and divide by 2.
If it is not: add new word into state_keyword array BUT if they are more than 15 words for one theme (which now are) I need to store just first 15 sorted by probabilities.
And this I need to do as effectively as possbile, because I need to do this every second so it must be FAST.
EDIT3:
Now I use this code:
var i, j, jj, l;
for(i = 0; i < 300; i++)
{
for(j = 0; j < 15; j++)
{
l = new_keywords[i].length;
for(jj = 0; jj < l; jj++)
{
if(state_keywords[i][j][0] === new_keywords[i][jj][0])
{
state_keywords[i][j][1] = (state_keywords[i][j][1] + new_keywords[i][jj][1]) / 2;
}
}
}
}
which is much faster then the previous one.

Why don't you make those arrays into objects with the strings as keys to the values? Then you can just just look up the words directly and get the values?
var wordlists = [
{
"word1":0.000199,
"word2":0.000102,
...
"word15":0.000102
},
...
{
"anotherword1":0.0032199,
"anotherword2":0.032302,
...
"anotherword15":0.0320102
}
]
and then lookup with
wordlists[0]["word2"] //0.000102