Error in eval (expr, envir, enc): could not find function "eval"

Question

I am working on a Caggle Digit Recognizer issue. When I tried this code, I got an error.

Error in eval (expr, envir, enc): could not find function "eval"

library(ggplot2) library(proto) library(readr) train <- data.frame(read_csv("../input/train.csv")) labels <- train[,1] features <- train[,-1] rowsToPlot <- sample(1:nrow(train), 49) rowToMatrix <- function(row) { intensity <- as.numeric(row)/max(as.numeric(row)) return(t(matrix((rgb(intensity, intensity, intensity)), 28, 28))) } geom_digit <- function (digits, labels) GeomRasterDigit$new(geom_params = list(digits=digits),stat = "identity", position = "identity", data = NULL, inherit.aes = TRUE) 

I get an error when starting the next segment.

 GeomRasterDigit <- proto(ggplot2:::GeomRaster, expr={ draw_groups <- function(., data, scales, coordinates, digits, ...) { bounds <- coord_transform(coordinates, data.frame(x = c(-Inf, Inf), y = c( - Inf, Inf)), scales) x_rng <- range(bounds$x, na.rm = TRUE) y_rng <- range(bounds$y, na.rm = TRUE) rasterGrob(as.raster(rowToMatrix(digits[data$rows,])), x_rng[1], y_rng[1], diff(x_rng), diff(y_rng),default.units = "native", just =c("left","bottom"), interpolate = FALSE) } }) 

Link to the full code: https://www.kaggle.com/benhamner/digit-recognizer/example-handwritten-digits/code

Answer 1

Take a look at the latest ggplot2 code on github. ggproto now replaces proto among other changes.

The code below should work fine.

  GeomRasterDigit <- ggproto(ggplot2:::GeomRaster, expr={ draw_groups <- function(., data, scales, coordinates, digits, ...) { bounds <- coord_transform(coordinates, data.frame(x = c(-Inf, Inf), y = c( - Inf, Inf)), scales) x_rng <- range(bounds$x, na.rm = TRUE) y_rng <- range(bounds$y, na.rm = TRUE) rasterGrob(as.raster(rowToMatrix(digits[data$rows,])), x_rng[1], y_rng[1], diff(x_rng), diff(y_rng),default.units = "native", just =c("left","bottom"), interpolate = FALSE) } }) 

There is a vignette near ggproto that is well read.