To all,
I am undergoing an analysis involving big matrices of about 30000x200 which
I have to handle in a more efficient way. So I would like some advice to
build such efficient function to deliver the following result:
- starting with 2 matrices of the same dimension (eg. A and B)
0 0 3 5 6 0 0 5
A= 0 0 6 4 B= 0 4 3 5
0 0 5 0 1 0 0 9
- the function should deliver a C matrix (same dimension too),
where at each position C(i,j), compares A and B.
if A(i,j)=0, than C(i,j)=0,
if A(i,j)!=0, than C(i,j)=B(i,j)
6 0 0 5
C= 0 0 3 5
0 0 0 0
Although not an expert I could build a function with 2 cycles (reading
columns and rows) which is not quick. Maybe you can help me in this
challenge.
Much thanks in advance,
Diogo André Alagador
Biodiversity & Global Change Lab, Museo Nacional de Ciencias Naturales,
CSIC, Madrid, España
Forest Research Centre, Instituto Superior de Agronomia, Universidade
Técnica de Lisboa, Lisboa, Portugal
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