R neuralNet: “non-conformable arguments”

Argh! I keep getting the following error when attempting to compute with my neural network:

> net.compute <- compute(net, matrix.train2)
Error in neurons[[i]] %*% weights[[i]] : non-conformable arguments

I can’t figure out what the problem is. Below I’ll provide you with an example data and formatting from my matrices and then I’ll show you the code I’m attempting to run.

• matrix.train1 is used for training the network> matrix.train1 (Intercept) survived pclass sexmale age sibsp parch fare embarkedC embarkedQ embarkedS 1 1 0 3 1 22.00 1 0 7.2500 0 0 1 2 1 1 1 0 38.00 1 0 71.2833 1 0 0 3 1 1 3 0 26.00 0 0 7.9250 0 0 1 4 1 1 1 0 35.00 1 0 53.1000 0 0 1 5 1 0 3 1 35.00 0 0 8.0500 0 0 1 6 1 0 3 1 999.00 0 0 8.4583 0 1 0 7 1 0 1 1 54.00 0 0 51.8625 0 0 1 8 1 0 3 1 2.00 3 1 21.0750 0 0 1 9 1 1 3 0 27.00 0 2 11.1333 0 0 1 10 1 1 2 0 14.00 1 0 30.0708 1 0 0 11 1 1 3 0 4.00 1 1 16.7000 0 0 1
• matrix.train2 is a slice of the training data used for testing the model> matrix.train2 (Intercept) pclass sexmale age sibsp parch fare embarkedC embarkedQ embarkedS 1 1 1 1 49.00 1 1 110.8833 1 0 0 2 1 3 1 42.00 0 0 7.6500 0 0 1 3 1 1 0 18.00 1 0 227.5250 1 0 0 4 1 1 1 35.00 0 0 26.2875 0 0 1 5 1 3 0 18.00 0 1 14.4542 1 0 0 6 1 3 1 25.00 0 0 7.7417 0 1 0 7 1 3 1 26.00 1 0 7.8542 0 0 1 8 1 2 1 39.00 0 0 26.0000 0 0 1 9 1 2 0 45.00 0 0 13.5000 0 0 1 10 1 1 1 42.00 0 0 26.2875 0 0 1 11 1 1 0 22.00 0 0 151.5500 0 0 1

The only real difference between the two matrices is that matrix.train2 doesn’t contain the survived column.

Here’s the R code I’m attempting to run:

#Build a matrix from training data 
matrix.train1 <- model.matrix(
  ~ survived + pclass + sex + age + sibsp + parch + fare + embarked, 
  data=train1
)

library(neuralnet)

#Train the neural net
net <- neuralnet(
  survived ~ pclass + sexmale + age + sibsp + parch + fare + embarkedC + 
  embarkedQ + embarkedS, data=matrix.train1, hidden=10, threshold=0.01
)

#Build a matrix from test data
matrix.train2 <- model.matrix(
  ~ pclass + sex + age + sibsp + parch + fare + embarked, 
  data=train2
)

#Apply neural net to test matrix 
net.results <- compute(
  net, matrix.train2
)

Error in neurons[[i]] %*% weights[[i]] : non-conformable arguments

Can anyone tell me what I’m doing wrong here?

Thanks!

---

Updates based on comments so far:

1. Using the solution from “Predicting class for new data using neuralnet” doesn’t seem to work.> net.compute <- compute(net, matrix.train2[,1:10]) Error in neurons[[i]] %*% weights[[i]] : non-conformable arguments
2. I’m manually putting my train1 and train2 data frames into matrices via model.matrix because if I don’t I get the following error:> Error in neurons[[i]] %*% weights[[i]] : requires numeric/complex matrix/vector arguments

Note: see the following thread for more details on why I’m using model.matrix: “Working with neuralnet in R for the first time: get “requires numeric/complex matrix/vector arguments” but don’t know how to correct“.