问题
I am working on a social network analysis assignment where I need to create a network from a matrix. I’m trying to create a matrix which shows what students are linked by classes they have in common, or not (a person-person matrix). I have wrangled the original data into the first iteration of a matrix and now want to multiply the matrix. My dataset and current matrix is a bigger version of the below:
names <- c("Tom", "Dick", "And", "Harry")
class <- c("cs1", "cs2", "cs3", "cs1")
count <- c(1, 1, 0, 1)
df = data.frame (names, class, count)
df2 <- spread(df, "class", "count")
When I run the matrix multiplication code I get this error message: Error in t(m) %*% m : requires numeric/complex matrix/vector arguments.
m <- as.matrix(df2)
m2 <- t(m) %*% m
A previous SO question and answer Matrix multiplication in R: requires numeric/complex matrix/vector arguments suggested the matrix needed to contain numeric or factor values, so I added the below code but I got the same the error message:
df2 %>% mutate_if(is.factor, as.character) -> df2
m <- as.matrix(df2)
m2 <- t(m) %*% m
If anyone can help me understand where I’m going wrong/ what the error message means here, I would appreciate it. Thank you!
P.S. Sorry for ugly code…new to R.
回答1:
This might help:
# fill NA with 0
df2[is.na(df2)] <- 0
# make row names the names of the people
row.names(df2) <- df2$names
df2 <- df2[,-1]
m <- as.matrix(df2)
m2 <- t(m) %*% m
来源：https://stackoverflow.com/questions/47804518/r-error-message-when-using-t-requires-numeric-complex-matrix-vector-argume