QVector various data format

jipe3001

I am wandering if I can use a multi dimensions QVector to store data with different format

Of course the QVector<QVector<QString> > is working but only for a same data format
( QString in this example)

Is there a way to define several data format (one per dimension) within the same Qvector ?

? Offline

Hi, and welcome to the Qt forum! How about using QVariant?

jipe3001

@Wieland

Thks for your help, that's really what I was looking for.
However I have another question regarding a QVector multi dimensions structure.

For instance a structure declared like this:

QVector< QVector< QVector< QVariant > > > test_vector_3d;
QVector< QVector< QVariant > > test_vector_2d;
QVector< QVariant > test_vector_1d;

QVariant qv1="item1";
QVariant qv2="item2";
QVariant qv3="item3";

test_vector_1d.append(qv1);
test_vector_1d.append(qv2);

test_vector_2d.append(test_vector_1d);

How can I append a third QVariant (qv3) to the test_vector_3d ?

Thks in advance

Chris Kawa

QVector< QVector< QVector< QVariant > > > is a vector of vectors of vectors of variants ie a 3D "cube" of QVariants.
What's the expected result i.e. to which dimension do you want the value appended? Because there's no one answer to this question. In other words which of the 8 corners of the cube should expand?

jipe3001

In my example only test_vector _2d is filled with values eg: test_vector_2d [item2] [item1]

My question is about how to load a value [item3] for the 3rd dimension
test_vector_3d [??] [item2] [item1]

It should be something like this:
test_vector_3d.append(test_vector_2d);

but I can't figure out how to append the QVariant qv3 to this array

Chris Kawa

@jipe3001 said:

test_vector_3d [??] [item2] [item1]

item1 and item2 are not indices so that's not what you have in your example. What you have is:

test_vector_1d[0] == item1
test_vector_1d[1] == item2

test_vector_2d[0][0] == item1
test_vector_2d[0][1] == item2

So again, what's your desired result. Any of these?

test_vector_3d[0][0][0] == item3
test_vector_3d[0][0][1] == item3
test_vector_3d[0][1][0] == item3
test_vector_3d[1][0][0] == item3
test_vector_3d[0][1][1] == item3
test_vector_3d[1][1][0] == item3
test_vector_3d[1][0][1] == item3
test_vector_3d[1][1][1] == item3

jipe3001

You are right I did not mean item x was an index but the value in the cell, my mistake !

Here is a screen shot of a debug session, showing the 1d,2d, 3d vectors after being initialize with append as described in my previous msg.

	v_records_1d	<3 éléments>	QVector<QVariant>
		[0]	(int) 1	QVariant
			d	struct QVariant::Private	QVariant::Private
				data	union QVariant::Private::Data	union QVariant::Private::Data
				type	2	unsigned int
				is_shared	0	unsigned int
				is_null	0	unsigned int
		[1]	(int) 9869	QVariant
		[2]	(double) 16.140000000000001	QVariant
	v_records_2d	<1 élément>	QVector<QVector<QVariant>>
		[0]	<3 éléments>	QVector<QVariant>
			[0]	(int) 1	QVariant
			[1]	(int) 9869	QVariant
			[2]	(double) 16.140000000000001	QVariant
	v_records_3d	<1 élément>	QVector<QVector<QVector<QVariant>>>
		[0]	<1 élément>	QVector<QVector<QVariant>>
			[0]	<3 éléments>	QVector<QVariant>
				[0]	(int) 1	QVariant
				[1]	(int) 9869	QVariant
				[2]	(double) 16.140000000000001	QVariant

We can see that
test_vector_3d[0][0][0] = 1
test_vector_3d[0][0][1] = 9869
test_vector_3d[0][0][2] = 16.14

My question is how can I enter values using append method for

test_vector_3d[0][1][0]
test_vector_3d[0][1][1]
test_vector_3d[0][1][2]

and

test_vector_3d[1][1][0]
test_vector_3d[1][1][1]
test_vector_3d[1][1][2]

Chris Kawa

To put something in item indexed [1] there's gotta be item [0] first, so to get

test_vector_3d[0][1][0]
test_vector_3d[0][1][1]
test_vector_3d[0][1][2]

you'd do:

QVector<QVariant> test_vector_1d;
test_vector_1d.append(1);
test_vector_1d.append(9869);
test_vector_1d.append(16.14);

QVector<QVector<QVariant>> test_vector_2d;
test_vector_2d.append(QVector<QVariant>()); //that's index [0]
test_vector_2d.append(test_vector_1d);      //that's index [1]

QVector<QVector<QVector<QVariant>>> test_vector_3d;
test_vector_3d.append(test_vector_2d);

Similarly, to get

test_vector_3d[1][1][0]
test_vector_3d[1][1][1]
test_vector_3d[1][1][2]

you'd do:

QVector<QVariant> test_vector_1d;
test_vector_1d.append(1);
test_vector_1d.append(9869);
test_vector_1d.append(16.14);

QVector<QVector<QVariant>> test_vector_2d;
test_vector_2d.append(QVector<QVariant>()); //that's index [0]
test_vector_2d.append(test_vector_1d);      //that's index [1]

QVector<QVector<QVector<QVariant>>> test_vector_3d;
test_vector_3d.append(QVector<QVector<QVariant>>()); //that's index [0]
test_vector_3d.append(test_vector_2d);               //that's index [1]

jipe3001

@Chris-Kawa

That's very clear now.

Thanks for your quick answers

I really appreciated your help