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digitalmars.D.learn - Re: Bidimensional dynamic array problem

Frits van Bommel Wrote:

 orgoton wrote:
 I have this
 struct Vertex{
 float z;
 Vertex vData[][];
 Somewhere later:
 foreach(Vertex strip[]; vData[]) strip.length=sizeY;

foreach(inout Vertex[] strip; vData) strip.length = sizeY; or just: foreach(inout strip; vData) strip.length = sizeY; Note: only the inout is significant, the rest is just nitpicking :P. If you don't specify 'inout', you're just modifying a local copy of the element... And IIRC something like "vData = new Vertex[][](sizeX, sizeY)" should replace that entire code sequence, initializing the outer array to an array of sizeX arrays of length sizeY.
 Here the array is initialized. So far, I think I haven't done anything
illegal. (SizeX and SizeY are runtime values, ushort vars). So first I say how
many strips I want, and next, I put in how many elements that strip will have.

You haven't done anything illegal, just something wrong ;). You haven't initialized the array the way you thought you did: it's just an array of _empty_ dynamic arrays at this point.
 ulong m;
 foreach (Vertex[] strip; vData)

(this loop doesn't require 'inout' since the array itself isn't modified, just the data it references)
       foreach (Vertex vertex; strip)

foreach(inout Vertex vertex; strip) (or: foreach(inout vertex; strip))
 Here I read the values from a file. First, I select a strip, and then go
through all the elements of that array and read their values. "m" is a counter
to see how many elements where read.
 The thing is, m=0 at the end of the loop. What did I do wrong?

Since you didn't initialize the elements of vData, their lengths are all still zero. So your inner loop is never executed.

That did it! Thanks a lot. I feel illuminated :P
Mar 06 2007