如何替换Oceananigans中FieldDataset的时间轴为自定义数组？

问题背景 #

使用Julia的Oceananigans海洋模型完成模拟后，通过JLD2OutputWriter将结果输出为jld2格式HDF5文件，文件包含多个随时间演化的3D变量。通过以下代码读取数据：

using Oceananigans

d4 = FieldDataset("./test4_lang.jld2")

d4.fields["u"].times

读取后d4.fields包含5个FieldTimeSeries对象：

julia> d4.fields
Dict{String, FieldTimeSeries} with 5 entries:
  "v"  => 32×32×32×103 FieldTimeSeries{InMemory} located at (Center, Face, Center) on CPU…
  "w"  => 32×32×33×103 FieldTimeSeries{InMemory} located at (Center, Center, Face) on CPU…
  "b"  => 32×32×32×103 FieldTimeSeries{InMemory} located at (Center, Center, Center) on CPU…
  "u"  => 32×32×32×103 FieldTimeSeries{InMemory} located at (Face, Center, Center) on CPU…
  "νₑ" => 32×32×32×103 FieldTimeSeries{InMemory} located at (Center, Center, Center) on CPU…

需要将这些FieldTimeSeries的时间轴替换为自定义数组（如1:103，长度103）。

解决方案 #

FieldTimeSeries是可变结构体，可直接遍历修改其times字段：

代码实现 #

# 定义自定义时间数组，示例为1到103的序列
custom_times = 1:103

# 遍历所有FieldTimeSeries对象，替换时间轴
for (_, fts) in d4.fields
    # 先校验长度一致性，避免错误
    @assert length(custom_times) == length(fts.times) "自定义时间数组长度与原时间轴不匹配"
    fts.times = custom_times
end

# 验证修改结果
println(d4.fields["u"].times)  # 输出应为1:103

替代写法（使用setproperty!） #

如果偏好显式调用结构体属性修改函数，也可以用setproperty!：

for (_, fts) in d4.fields
    @assert length(custom_times) == length(fts.times) "自定义时间数组长度与原时间轴不匹配"
    setproperty!(fts, :times, custom_times)
end

内容的提问来源于stack exchange，提问作者Kenneth Lee