Can't multiply sparse logical matrices?

Is there a way to multiply sparse logical matrices? I guess I am looking for a space efficient way to multiply matrices that contain only 0/1?
>> m = magic(5)
m =
17 24 1 8 15
23 5 7 14 16
4 6 13 20 22
10 12 19 21 3
11 18 25 2 9
>> a = m>5
a =
1 1 0 1 1
1 0 1 1 1
0 1 1 1 1
1 1 1 1 0
1 1 1 0 1
>> b = m>10
b =
1 1 0 0 1
1 0 0 1 1
0 0 1 1 1
0 1 1 1 0
1 1 1 0 0
>> a+b
ans =
2 2 0 1 2
2 0 1 2 2
0 1 2 2 2
1 2 2 2 0
2 2 2 0 1
>> a*b
Error using *
Both logical inputs must be scalar.
To compute elementwise TIMES, use TIMES (.*) instead.

Respuestas (2)

the cyclist
the cyclist el 13 de Jun. de 2012

1 voto

The short answer is "no". However ...
I asked about multiplication of logical matrices a while back. There were some answers that might be helpful to you in the thread:
Thomas Richner
Thomas Richner el 12 de Dic. de 2017
Editada: Thomas Richner el 12 de Dic. de 2017

0 votos

I too would love to multiply sparse logical matrices. I was completely surprised it wasn't implemented. The solution is to convert the smaller matrix to a sparse double with double(). Also note that sparse singles don't exist. I imagine as Matlab tries to keep pace with Deep Learning, they will need to add sparse singles, sparse logical multiplication, and half precision types.

Categorías

Más información sobre Sparse Matrices en Centro de ayuda y File Exchange.

Etiquetas

Preguntada:

el 13 de Jun. de 2012

Editada:

el 12 de Dic. de 2017

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by