使用ncdf4包从.csv文件到.nc文件（ncvar_put中出错）

我正在尝试从.csv文件写入.nc文件

这是我的.csv表df的一部分

你们可以看到，我有两个维度和一个变量

这是我正在使用的代码：

xvals <- unique(df$long)
xvals <- xvals[order(xvals)]
yvals = unique(df$lat)
yvals <- yvals[order(yvals)] 

lon <- ncdim_def("longitude", "degrees", xvals)
lat <- ncdim_def("latitude", "degrees", yvals)

var_elev <- ncvar_def("elev", "m above sea", 
                      list(lon, lat), NA) 

ncnew <- nc_create('elev.nc', var_elev)

ncvar_put(ncnew, "elev", df$elev, count = c(35, 51))

有关我的维度的更多信息：

yvals唯一值：

yvals
 [1] -15.001234 -14.751234 -14.501234 -14.251234 -14.001234
 [6] -13.751234 -13.501234 -13.251234 -13.001234 -12.751234
[11] -12.501234 -12.251234 -12.001234 -11.751234 -11.501234
[16] -11.251234 -11.001234 -10.751234 -10.501234 -10.251234
[21] -10.001234  -9.751234  -9.501234  -9.251234  -9.001234
[26]  -8.751234  -8.501234  -8.251234  -8.001234  -7.751234
[31]  -7.501234  -7.251234  -7.001234  -6.751234  -6.501234
[36]  -6.251234  -6.001234  -5.751234  -5.501234  -5.251234
[41]  -5.001234  -4.751234  -4.501234  -4.251234  -4.001234
[46]  -3.751234  -3.501234  -3.251234  -3.001234  -2.751234
[51]  -2.501234

xvals
 [1] -50.49206 -50.24206 -49.99206 -49.74206 -49.49206 -49.24206
 [7] -48.99206 -48.74206 -48.49206 -48.24206 -47.99206 -47.74206
[13] -47.49206 -47.24206 -46.99206 -46.74206 -46.49206 -46.24206
[19] -45.99206 -45.74206 -45.49206 -45.24206 -44.99206 -44.74206
[25] -44.49206 -44.24206 -43.99206 -43.74206 -43.49206 -43.24206
[31] -42.99206 -42.74206 -42.49206 -42.24206 -41.99206

xVAL唯一值：

yvals
 [1] -15.001234 -14.751234 -14.501234 -14.251234 -14.001234
 [6] -13.751234 -13.501234 -13.251234 -13.001234 -12.751234
[11] -12.501234 -12.251234 -12.001234 -11.751234 -11.501234
[16] -11.251234 -11.001234 -10.751234 -10.501234 -10.251234
[21] -10.001234  -9.751234  -9.501234  -9.251234  -9.001234
[26]  -8.751234  -8.501234  -8.251234  -8.001234  -7.751234
[31]  -7.501234  -7.251234  -7.001234  -6.751234  -6.501234
[36]  -6.251234  -6.001234  -5.751234  -5.501234  -5.251234
[41]  -5.001234  -4.751234  -4.501234  -4.251234  -4.001234
[46]  -3.751234  -3.501234  -3.251234  -3.001234  -2.751234
[51]  -2.501234

xvals
 [1] -50.49206 -50.24206 -49.99206 -49.74206 -49.49206 -49.24206
 [7] -48.99206 -48.74206 -48.49206 -48.24206 -47.99206 -47.74206
[13] -47.49206 -47.24206 -46.99206 -46.74206 -46.49206 -46.24206
[19] -45.99206 -45.74206 -45.49206 -45.24206 -44.99206 -44.74206
[25] -44.49206 -44.24206 -43.99206 -43.74206 -43.49206 -43.24206
[31] -42.99206 -42.74206 -42.49206 -42.24206 -41.99206

elev列有959个唯一值

此外，我不确定对尺寸进行重新排序是否会使long、lat和elev之间的对应关系正确。无论如何，我完全不知道如何解决这个问题

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谢谢大家

您正在尝试使用ncdim_def定义二维数组，但只将一维向量传递给数据集。您需要将数据帧的观测值转换为二维数组。这可以通过tidyr完成：

library(tidyr)
# Example df with same names
df <- data.frame(long = rep(1:10,2), lat = 1:40, elev = 1:40)
# Creates a 2D array
df_new <- tidyr::pivot_wider(df, names_from = long, values_from = elev)
df_new <- df_new[,-1]

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嗨，在最后一行，我认为elev应该是elev，即字符串。你能说出var_elev的大小和df$elev的大小吗？它们显然不匹配。是的，当然，我进行了更正并更新了错误消息。同样的错误也会出现，但是数字不同。另外，var_elev$varsize返回3551。我试图实现您的解决方案，但没有成功。我得到了以下错误：ncvar_putncnew中的错误，varid=elev，vals=df_new:list对象无法强制在ncvar_put函数调用中键入'double'，将df_new更改为as.matrixdf_new，我忘记了这一点。

ncvar_put(ncnew, elev, as.matrix(df_new))