Re: What is the replacement for deprecated array removal
On Monday, 18 November 2019 at 21:25:12 UTC, kerdemdemir wrote:
It is a bit weird that such a general case like removing list
of elements does not work.
And I really do not know the real use of
[0,1,2,3].remove(1,2,3). I mean in unit test it looks cool but
in real life you will have dynamically calculated indexes.
Erdem
It seems like a defect in phobos to me as well. Fortunately phobos
is written in D so you can just copy&paste this into your code:
https://github.com/dlang/phobos/blob/master/std/algorithm/mutation.d#L2160
however, it still doesn't return the same thing as
x.remove(1,2,3).
... maybe it'd be simpler to drop down to C-style D?
// no checks for out-of-bounds or unsorted offsets
void myRemove(ref int[] array, int[] offsets) {
int from, to, offset;
while (from < array.length) {
if (offset < offsets.length && from == offsets[offset]) {
++offset;
++from;
} else if (from == to) {
++to;
++from;
} else {
array[to++] = array[from++];
}
}
array.length = to;
}
unittest {
int[] x = [1, 2, 3];
int[] y = x.dup, z = x.dup, q = x.dup;
myRemove(x, [0]);
myRemove(y, []);
myRemove(z, [2]);
myRemove(q, [1, 2]);
assert(x == [2, 3]);
assert(y == [1, 2, 3]);
assert(z == [1, 2]);
assert(q == [1]);
}
Perhaps it's nice to have the option?
Re: What is the replacement for deprecated array removal
On Monday, 18 November 2019 at 21:14:53 UTC, Steven Schveighoffer wrote: On 11/18/19 3:53 PM, kerdemdemir wrote: Is there any way to remove list of elements efficiently with a dynamical array? It seems kind of silly that it's not allowed, but maybe it will be possible after the deprecation is removed. But you could do something like this: list = list.remove!(a => removeList.canFind(a)); This is going to suck. Because it's O(n^2). Should be O(n + m) way to do it (assuming you have a sorted index list). Or is there anyway converting a dynamical array into a form which is like a AliasSeq? An AliasSeq is a compile-time construct, and cannot be created from a runtime array. -Steve Thanks for awesome answers man , Yes that sucks real hard because unlike that dummy example in my real case == compression will be too expensive I can't simply use canFind on every index. I guess I need to recreate a new dynamical array each time which is also horrible. It is a bit weird that such a general case like removing list of elements does not work. And I really do not know the real use of [0,1,2,3].remove(1,2,3). I mean in unit test it looks cool but in real life you will have dynamically calculated indexes. Erdem
Re: What is the replacement for deprecated array removal
On 11/18/19 3:53 PM, kerdemdemir wrote: Is there any way to remove list of elements efficiently with a dynamical array? It seems kind of silly that it's not allowed, but maybe it will be possible after the deprecation is removed. But you could do something like this: list = list.remove!(a => removeList.canFind(a)); This is going to suck. Because it's O(n^2). Should be O(n + m) way to do it (assuming you have a sorted index list). Or is there anyway converting a dynamical array into a form which is like a AliasSeq? An AliasSeq is a compile-time construct, and cannot be created from a runtime array. -Steve
Re: What is the replacement for deprecated array removal
On Monday, 18 November 2019 at 20:48:40 UTC, kerdemdemir wrote: On Monday, 18 November 2019 at 20:37:50 UTC, Steven Schveighoffer wrote: If I follow the code correctly, it's treating your array as a tuple of pos/len to remove. So it looks like your code is equivalent to remove(tuple(0, 2)); Which is probably not what you want. This probably explains why it's being deprecated, it's too confusing to the compiler. And looking at git blame goes back to this PR: https://github.com/dlang/phobos/pull/6154 -Steve Sorry to be horrible at explaining but remove(tuple(0, 2)); is not what I want. I have an array which goes from 0 to 5. And I want to remove odd numbers. remove(tuple(0, 2)); defines a starting index and a ending index but I need to delete not consecutive elements. In the case of odd number from 0 to 5 that will be 1, 3 and 5 . It is so weird when you type it is allowed like remove(1, 3, 5) but unexpectedly remove([1,3,5]) does not work the same way. I think if I can convert [1,3,5] to a AliasSeq that could be ok also. Erdem I read your message again now and I see that you weren't suggesting remove(tuple(0, 2)) but you were pointing out it is not what I want as well. Is there any way to remove list of elements efficiently with a dynamical array? Or is there anyway converting a dynamical array into a form which is like a AliasSeq? Erdem
Re: What is the replacement for deprecated array removal
On Monday, 18 November 2019 at 20:37:50 UTC, Steven Schveighoffer wrote: If I follow the code correctly, it's treating your array as a tuple of pos/len to remove. So it looks like your code is equivalent to remove(tuple(0, 2)); Which is probably not what you want. This probably explains why it's being deprecated, it's too confusing to the compiler. And looking at git blame goes back to this PR: https://github.com/dlang/phobos/pull/6154 -Steve Sorry to be horrible at explaining but remove(tuple(0, 2)); is not what I want. I have an array which goes from 0 to 5. And I want to remove odd numbers. remove(tuple(0, 2)); defines a starting index and a ending index but I need to delete not consecutive elements. In the case of odd number from 0 to 5 that will be 1, 3 and 5 . It is so weird when you type it is allowed like remove(1, 3, 5) but unexpectedly remove([1,3,5]) does not work the same way. I think if I can convert [1,3,5] to a AliasSeq that could be ok also. Erdem
Re: What is the replacement for deprecated array removal
On 11/18/19 3:01 PM, kerdemdemir wrote:
int[] removeList;
for ( int i = 0; i < tempMap[0].length; i++ )
{
if ( i%2 == 0 )
removeList ~=i;
}
writeln(removeList); (prints 0,2,4)
tempMap[1].remove(0,2,4);
tempMap[2].remove(removeList);
tempMap[3].remove(tuple(0,1),tuple(2,3),tuple(4,5) );
Even weirder(at least for me)
int[] removeList is [0,2,4]
And .remove returns different results for .remove(0,2,4); and
..remove(removeList)
Is there anyway to convert int[] to a sequence like 0,2,4
Erdem
If I follow the code correctly, it's treating your array as a tuple of
pos/len to remove.
So it looks like your code is equivalent to
remove(tuple(0, 2));
Which is probably not what you want.
This probably explains why it's being deprecated, it's too confusing to
the compiler.
And looking at git blame goes back to this PR:
https://github.com/dlang/phobos/pull/6154
-Steve
Re: What is the replacement for deprecated array removal
int[] removeList;
for ( int i = 0; i < tempMap[0].length; i++ )
{
if ( i%2 == 0 )
removeList ~=i;
}
writeln(removeList); (prints 0,2,4)
tempMap[1].remove(0,2,4);
tempMap[2].remove(removeList);
tempMap[3].remove(tuple(0,1),tuple(2,3),tuple(4,5) );
Even weirder(at least for me)
int[] removeList is [0,2,4]
And .remove returns different results for .remove(0,2,4); and
.remove(removeList)
Is there anyway to convert int[] to a sequence like 0,2,4
Erdem
What is the replacement for deprecated array removal
I know my example can be shortened but please excuse me that I am
pasting directly
import std.stdio;
import std.math;
import std.range;
import std.algorithm;
import std.typecons;
int[][4] tempMap;
void main()
{
int[] temp = [ 1, 2, 3 , 4 ,5 ];
tempMap[0] = temp.dup;
tempMap[1] = temp.dup;
tempMap[2] = temp.dup;
tempMap[3] = temp.dup;
int[] removeList;
for ( int i = 0; i < tempMap.length; i++ )
{
if ( i%2)
removeList ~=i;
}
tempMap[1].remove(removeList);
writeln(tempMap);
}
Results with that warning:
onlineapp.d(24): Deprecation: function
std.algorithm.mutation.remove!(cast(SwapStrategy)2, int[],
int[]).remove is deprecated
How can I remove a list of indexes with remove ?
Erdem
