y, c, and f only exist in the context of mac2
If you want to use them, you'll have to write mac2$y, mac2$c, or mac2$f (or
the [[ versions mac2[["y"]], mac2[["c"]], or mac2[["f"]])
Combining that with index i would then look like mac2$y[[i]] or mac2[[i,
"y"]]
Also, I think you want to use aes_string instead of aes (since you want
those expressions within aes to be evaluated)
Something like this seems to work for me:
`%>%` <- magrittr::`%>%`
writeLines(FILE <- tempfile(), text =
r"{y,c,f
hwy,cyl,hwy_cyl2
cty,class,cty_class2}")
mac2 <- readr::read_csv(FILE)
for (i in seq_len(nrow(mac2))) {
ggplt <- ggplot2::mpg %>%
dplyr::filter(hwy < 35) %>%
ggplot2::ggplot(
ggplot2::aes_string(
x = "displ",
y = mac2[[i, "y"]],
color = mac2[[i, "c"]]
)
) +
ggplot2::geom_point() +
ggplot2::ylab(mac2[[i, "y"]]) +
ggplot2::guides(
color = ggplot2::guide_legend(title = mac2[[i, "c"]])
)
ggplot2::ggsave(
filename = tempfile(
mac2[[i, "f"]],
fileext = ".jpg"
),
plot = ggplt,
width = 9, height = 6, dpi = 1200
)
}
unlink(FILE)
runs fine on my computer, but might look more like this for you:
library(magrittr)
library(ggplot2)
library(dplyr)
library(readr)
mac2 <- read_csv("C:/temp/mac2.csv")
for (i in seq_len(nrow(mac2))) {
ggplt <- mpg %>%
filter(hwy < 35) %>%
ggplot(
aes_string(
x = "displ",
y = mac2[[i, "y"]],
color = mac2[[i, "c"]]
)
) +
geom_point() +
ylab(mac2[[i, "y"]]) +
guides(
color = guide_legend(title = mac2[[i, "c"]])
)
ggsave(
filename = paste0("C:/temp/", mac2[[i, "f"]], ".jpg"),
plot = ggplt,
width = 9, height = 6, dpi = 1200
)
}
try reading through aes and aes_string, and keep in mind that columns in
data frames aren't R variables (where they are in Excel). If you want to
use columns like they are variables, you can try using `with`. For example:
library(magrittr)
library(ggplot2)
library(dplyr)
library(readr)
mac2 <- read_csv("C:/temp/mac2.csv")
for (i in seq_len(nrow(mac2))) {
with(mac2[i, ], {
ggplt <- mpg %>%
filter(hwy < 35) %>%
ggplot(
aes_string(
x = "displ",
y = y,
color = c
)
) +
geom_point() +
ylab(y) +
guides(
color = guide_legend(title = c)
)
ggsave(
filename = paste0("C:/temp/", f, ".jpg"),
plot = ggplt,
width = 9, height = 6, dpi = 1200
)
})
}
On Fri, Dec 24, 2021 at 4:48 PM Kai Yang via R-help <r-help@r-project.org>
wrote:
> Hello Team,
> I create a csv file (mac2) to save parameter values. the file looks like:
>
> y,c,f
> hwy,cyl,hwy_cyl2
> cty,class,cty_class2
>
> Then I load the file into R and apply the parameters y, c, f in for loop,
> see my code below:
> library(ggplot2)
> library(tidyverse)
> library(readr)
> mac2 <- read_csv("C:/temp/mac2.csv")
> View(mac2)
> for (i in seq(nrow(mac2))){
> mpg %>%
> filter(hwy <35) %>%
> ggplot(aes(x = displ, y = get(y[i]), color = get(c[i]) )) +
> geom_point()+
> ylab(y[i]) +
> guides(color = guide_legend(title = c[i]))
> ggsave(paste0("c:/temp/",f[i],".jpg"),width = 9, height = 6, dpi = 1200,
> units = "in")
> }
>
> but I got an error message: "Error in dots_list(..., title = title,
> subtitle = subtitle, caption = caption, : object 'y' not found"
> Does anyone know how to fix the problem?
> Thanks,
> Kai
>
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
[[alternative HTML version deleted]]
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
