lookup tables

var redraw = [
[0, 0, 1, "north"],
[1, 1, 1, "north east"],
[2, 1, 0, "east"],
[3, 1,-1, "south east"],
[4, 0,-1, "south"],
[5,-1,-1, "south west"],
[6,-1, 0, "west"],
[7,-1, 1, "north west"],
];

With teh following table, it is easy to convert from a number row
reference to text

d = redraw[row][3]

But if I have text, is there an easy way to lookup the other columns in
this kind of table?


--
--
Fabian
Visit my website often and for long periods!
http://www.lajzar.co.uk

"Fabian" <lajzar (AT) hotmail (DOT) com> schreef in bericht
news:bokemu$1f2n90$2 (AT) ID-174912 (DOT) news.uni-berlin.de...

But if I have text, is there an easy way to lookup the other columns in
this kind of table?

// Note that I have removed the last comma in the definition of redraw
var redraw = [
[0, 0, 1, "north"],
[1, 1, 1, "north east"],
[2, 1, 0, "east"],
[3, 1,-1, "south east"],
[4, 0,-1, "south"],
[5,-1,-1, "south west"],
[6,-1, 0, "west"],
[7,-1, 1, "north west"]
];

function findRow(text) {
for (var i = 0; i < redraw.length; i++) {
if (redraw[i][redraw[i].length-1] == text)
return redraw[i];
}
return false;
}

var row = findRow("north east");
if (row) {
alert(row.join(', '));
} else {
alert('not found');
}


JW

Janwillem Borleffs hu kiteb:

"Fabian" <lajzar (AT) hotmail (DOT) com> schreef in bericht
news:bokemu$1f2n90$2 (AT) ID-174912 (DOT) news.uni-berlin.de...

But if I have text, is there an easy way to lookup the other columns
in this kind of table?


// Note that I have removed the last comma in the definition of redraw

Duly noted.

var redraw = [
[0, 0, 1, "north"],
[1, 1, 1, "north east"],
[2, 1, 0, "east"],
[3, 1,-1, "south east"],
[4, 0,-1, "south"],
[5,-1,-1, "south west"],
[6,-1, 0, "west"],
[7,-1, 1, "north west"]
];

function findRow(text) {
for (var i = 0; i < redraw.length; i++) {
if (redraw[i][redraw[i].length-1] == text)

In the specific case of this table, can I replace that line above with
the following and have the same effect:

if (redraw[i][3] == text)

return redraw[i];

Presumably, if I know the exact column I want from the table, I can use
instead:

return redraw[i][ column_number ]

}
return false;
}

--
--
Fabian
Visit my website often and for long periods!
http://www.lajzar.co.uk

"Fabian" <lajzar (AT) hotmail (DOT) com> writes:

With teh following table, it is easy to convert from a number row
reference to text

d = redraw[row][3]

But if I have text, is there an easy way to lookup the other columns in
this kind of table?

No. You have to run through the array to find the match.

You can build a new dictionary object to make it faster. Then you only
have to run through the array once.

---
var redrawDictionary = new Object();
for (var i=0;i<redraw.length;i++) {
redrawDictionary[redraw[i][3]] = i;
}
---
You can then make a lookup:
---
var row = redrawDictionary["south"]; // row == 4
---
/L
--
Lasse Reichstein Nielsen - lrn (AT) hotpop (DOT) com
DHTML Death Colors: <URL:http://www.infimum.dk/HTML/rasterTriangleDOM.html>
'Faith without judgement merely degrades the spirit divine.'

"Fabian" <lajzar (AT) hotmail (DOT) com> schreef in bericht
news:bol7e1$1g0vb3$1 (AT) ID-174912 (DOT) news.uni-berlin.de...

In the specific case of this table, can I replace that line above with
the following and have the same effect:

if (redraw[i][3] == text)

Yes, when the arrays have a fixed length

Presumably, if I know the exact column I want from the table, I can use
instead:

return redraw[i][ column_number ]

Shure.


JW