python - 使用python查找CSV文件每一列的最小值

Question

我创建了一个程序来查找 CSV 文件每一行的最小值，现在我想对每一列执行相同的操作，但是我一直无法这样做。如有任何建议，我们将不胜感激。

       #Import and convert csv
  import csv
  data = []
  with open(file,"r") as f:
        reader = csv.reader(f, delimiter=',')
  #make sure csv uses "." not "," !!!!!
        nump = 0 
        for row in reader:
              floatrow = []
              for val in row:
                    floatrow.append(float(val))
              nump += len(floatrow)
              data.append(floatrow)

  #Calculates minimum of each row, minimum and sum of row           
  minrr = []
  sum1 = 0.0
  for row in data:
      list2 = (min (filter(None, row)))
      minrr.append(list2)
      sum1 += sum(row)

Answer 1

您可以只使用 python 内置命令和通过压缩所有行实现的转置，如下所示:

import csv
a = []
with open('path/to/file.csv',"r") as f:
        reader = csv.reader(f, delimiter=',')
        for row in reader:
            #turn all input to floats
            row = map (float, row)
            #append the entire row to create list of lists
            a.append(row)
# Transpose a into b
b = zip (*a)
# Now min of row will be min of col in a
for line in b:
    print min(line)