np.loadtxt的float转换怎么去

Question

之前问过的时间字符串YYYY-mm-dd转datetime解决了，解决方法是把转换部分单独提出去了

但是np.loadtxt还显示不能转换...我寻思也没有写loadtxt转换呀,怎么让loadtxt不自己转换...

一直报ValueError: could not convert string to float: '2020-04-03',

报警信息全文:

File "D:\Users\PycharmProjects\temp.py", line 178, in readCsv
    TimeStr = numpy.loadtxt("D:\File.csv", delimiter=",", unpack=True, skiprows=1)
  File "D:\Python39\lib\site-packages\numpy\lib\npyio.py", line 1146, in loadtxt
    for x in read_data(_loadtxt_chunksize):
  File "D:\Python39\lib\site-packages\numpy\lib\npyio.py", line 997, in read_data
    items = [conv(val) for (conv, val) in zip(converters, vals)]
  File "D:\Python39\lib\site-packages\numpy\lib\npyio.py", line 997, in <listcomp>
    items = [conv(val) for (conv, val) in zip(converters, vals)]
  File "D:\Python39\lib\site-packages\numpy\lib\npyio.py", line 734, in floatconv
    return float(x)

TimeStr = numpy.loadtxt("D:\File.csv", delimiter=",", unpack=True, skiprows=1)
NumStr = numpy.loadtxt("D:\File.csv", delimiter=",", unpack=True, skiprows=1)
datetime.strptime(datetime.isoformat(TimeStr).split('.')[0], '%Y-%m-%d')
datetime.strptime(datetime.isoformat(NumStr).split('.')[0], '%Y-%m-%d')

...顺便问一下,np的load和loadtxt有什么不同之处

Answer 1

np.loadtxt函数默认情况下会将读取的数据转换为float类型。如果需要更精确的浮点数表示，可以使用np.loadtxt的dtype参数来指定所需的数据类型，例如使用np.float64类型：

import numpy as np

data = np.loadtxt('data.txt', dtype=np.float64)

如果需要将读取的数据转换为其他类型，可以使用astype方法。例如将float类型转换为int类型：

import numpy as np

data = np.loadtxt('data.txt')
data = data.astype(np.int32)