Error in `residuals(<mod>)` with scalar on function regression

[LucasKook]

Problem description

In the FDboost() example on scalar-on-function regression, calling residuals(mod2) throws an error complaining that

Error in matrix(object$resid(), nrow = object$ydim[1]) : 
  non-numeric matrix extent

since for one-dimensional responses, object$ydim[1] is NULL. mod$resid() itself works fine.

Reprex

Here is the example code:

library("FDboost")

data("fuelSubset", package = "FDboost")

## center the functional covariates per observed wavelength
fuelSubset$UVVIS <- scale(fuelSubset$UVVIS, scale = FALSE)
fuelSubset$NIR <- scale(fuelSubset$NIR, scale = FALSE)

## to make mboost:::df2lambda() happy (all design matrix entries < 10)
## reduce range of argvals to [0,1] to get smaller integration weights
fuelSubset$uvvis.lambda <- with(fuelSubset, (uvvis.lambda - min(uvvis.lambda)) /
  (max(uvvis.lambda) - min(uvvis.lambda)))
fuelSubset$nir.lambda <- with(fuelSubset, (nir.lambda - min(nir.lambda)) /
  (max(nir.lambda) - min(nir.lambda)))

## model fit with scalar response
## include no intercept as all base-learners are centered around 0
mod2 <- FDboost(
  heatan ~ bsignal(UVVIS, uvvis.lambda, knots = 40, df = 4, check.ident = FALSE)
    + bsignal(NIR, nir.lambda, knots = 40, df = 4, check.ident = FALSE),
  timeformula = NULL, data = fuelSubset, control = boost_control(mstop = 200)
)

residuals(mod2)

Session Info

R version 4.4.2 (2024-10-31)
Platform: x86_64-pc-linux-gnu
Running under: Ubuntu 22.04.5 LTS

Matrix products: default
BLAS:   /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.10.0 
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.10.0

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C               LC_TIME=de_AT.UTF-8       
 [4] LC_COLLATE=en_US.UTF-8     LC_MONETARY=de_AT.UTF-8    LC_MESSAGES=en_US.UTF-8   
 [7] LC_PAPER=de_AT.UTF-8       LC_NAME=C                  LC_ADDRESS=C              
[10] LC_TELEPHONE=C             LC_MEASUREMENT=de_AT.UTF-8 LC_IDENTIFICATION=C       

time zone: Europe/Vienna
tzcode source: system (glibc)

attached base packages:
[1] parallel  stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] FDboost_1.1-2  mboost_2.9-11  stabs_0.6-4    nvimcom_0.9.58

loaded via a namespace (and not attached):
 [1] Formula_1.2-5     mgcv_1.9-1        Matrix_1.7-0      lattice_0.22-5    inum_1.0-5       
 [6] rpart_4.1.23      splines_4.4.2     zoo_1.8-12        libcoin_1.0-10    nnls_1.6         
[11] mvtnorm_1.3-2     gamboostLSS_2.0-7 partykit_1.2-20   grid_4.4.2        compiler_4.4.2   
[16] tools_4.4.2       nlme_3.1-165      survival_3.7-0    quadprog_1.5-8    MASS_7.3-60.2    

[LucasKook]

PR #28 should do the trick :-)

Cheers, Lucas

[Almond-S]

Thanks, Lucas, for fixing!!