使用vector中的值转换2D numpy数组中的NaN值

Question

我有一个2D numpy数组，想要用1D数组中的相应值替换每一行中的每个NaN。例如，这个矩阵：

[[1.  2. NaN]
 [4.  5.  6.]
 [NaN NaN 9.]]

使用向量[3. 7. 8.]将转换为：

[[1. 2. 8.]
 [4. 5. 6.]
 [3. 7. 9.]]

如何在不迭代索引的情况下执行此操作？

Answer 1

使用numpy.where并广播：

.box

numpy.isnan()为您提供一系列布尔值，其中NaN的值为'[!] There was an error parsing 'Gemfile': You cannot specify the same gem twice with different version requirements. You specified: sdoc (~> 0.4.0) and sdoc (>= 0). BUndlr cannot continue. from c:/Users/MacKenzie/Documents/Programming/Projects/odot/Gemfile:16 ------------------------------------ # Windows does not include zoneinfo files, so bundle the tzinfo-data gem > gem 'tzinfo-data' platforms: [:mingw, :mswin, :x64_mingw, :jruby} source 'https://rubygems.org' -------------------------------------' ，>>> a = np.array([[1., 2., np.nan], [4., 5., 6.], [np.nan, np.nan, 9.]]) >>> v = np.array([3, 7, 8]) >>> np.where(np.isnan(a), v, a) array([[ 1., 2., 8.], [ 4., 5., 6.], [ 3., 7., 9.]]) 为

。