我正在使用R循环遍历数据框的列,并绘制结果分析图。脚本运行时我没有收到任何错误,但它生成了一个无法打开的pdf。
如果我运行脚本的内容,它可以正常工作。我想知道循环的速度是否有问题,所以我试图强迫它暂停。这似乎没有什么区别。我对人们有任何建议感兴趣,而且我对R也很陌生,所以我也欢迎如何改进方法的建议。感谢。
for (i in 2:22) {
# Organise data
pop_den_z = subset(pop_den, pop_den[i] != "0") # Remove zeros
y = pop_den_z[,i] # Get y col
x = pop_den_z[,1] # get x col
y = log(y) # Log transform
# Regression
lm.0 = lm(formula = y ~ x) # make linear model
inter = summary(lm.0)$coefficients[1,1] # Get intercept
slop = summary(lm.0)$coefficients[2,1] # Get slope
# Write to File
a = c(i, inter, slop)
write(a, file = "C:/pop_den_coef.txt", ncolumns = 3, append = TRUE, sep = ",")
## Setup pdf
string = paste("C:/LEED/results/Images/R_graphs/Pop_den", paste(i-2), "City.pdf")
pdf(string, height = 6, width = 9)
p <- qplot(
x, y,
xlab = "Radius [km]",
ylab = "Population Density [log(people/km)]",
xlim = x_range,
main = "Analysis of Cities"
)
# geom_abline(intercept,slope)
p + geom_abline(intercept = inter, slope = slop, colour = "red", size = 1)
Sys.sleep(5)
### close the PDF file
dev.off()
}
答案 0 :(得分:10)
该行应为
print(p + geom_abline(intercept = inter, slope = slop, colour = "red", size = 1))
在pdf设备中,ggplot(和lattice)仅在显式打印时写入文件。