如何找到數組中每個x值的最小值？

Question

path = ("C:/Users/Calum/AppData/Local/Programs/Python/Python35-32/Python Programs/PV Data/Monthly Data/brunel-11-2016.csv") 
with open (path) as f: 
    readCSV = csv.reader((islice(f, 0, 8352)), delimiter = ';') 
    irrad_bru1 = [] 

    for row in readCSV: 
     irrad1 = row[1] 

     irrad_bru1.append(irrad1) 

irrad_bru1 = ['0' if float(x)<0 else x for x in irrad_bru1] 
bru_arr1 = np.asarray(irrad_bru1).astype(np.float) 

rr_bru1 = -np.diff(bru_arr1) 

我想在每200個條目中找到數組rr_bru1中的最小值，我該如何去做呢？

Answer 1

您可以使用np.minimum.reduceat：

np.minimum.reduceat(a, np.arange(0, len(a), 200)) 

Answer 2

一種方法使用切片做到這一點：

的Python 3

n = 200 
[min(mylist[i:i + n]) for i in range(0, len(mylist), n)] 

的Python 2

n = 200 
[min(mylist[i:i + n]) for i in xrange(0, len(mylist), n)]