python语句iloc里面的值是负一是什么意思，iloc[:-1:] python中iloc 和loc ix的区别
Python Pandas\u7684iloc\u7591\u95ee-1\u6307\u7684\u662f\u6700\u540e\u4e00\u9879\u3002
testList = [1,2,3,4]
testList [-1] === 4 (true)
loc \u5728index\u7684\u6807\u7b7e\u4e0a\u8fdb\u884c\u7d22\u5f15,\u8303\u56f4\u5305\u62ecstart\u548cend\u3002
iloc \u5728index\u7684\u4f4d\u7f6e\u4e0a\u8fdb\u884c\u7d22\u5f15,\u4e0d\u5305\u62ecend.\u3002
ix \u662f iloc \u548c loc\u7684\u5408\u4f53\u3002
Python(\u82f1\u8bed\u53d1\u97f3:/ˈpaɪ\u03b8ən/), \u662f\u4e00\u79cd\u9762\u5411\u5bf9\u8c61\u3001\u89e3\u91ca\u578b\u8ba1\u7b97\u673a\u7a0b\u5e8f\u8bbe\u8ba1\u8bed\u8a00\uff0c\u7531Guido van Rossum\u4e8e1989\u5e74\u5e95\u53d1\u660e\uff0c\u7b2c\u4e00\u4e2a\u516c\u5f00\u53d1\u884c\u7248\u53d1\u884c\u4e8e1991\u5e74\uff0cPython \u6e90\u4ee3\u7801\u540c\u6837\u9075\u5faa GPL(GNU General Public License)\u534f\u8bae\u3002Python\u8bed\u6cd5\u7b80\u6d01\u800c\u6e05\u6670\uff0c\u5177\u6709\u4e30\u5bcc\u548c\u5f3a\u5927\u7684\u7c7b\u5e93\u3002\u5b83\u5e38\u88ab\u6635\u79f0\u4e3a\u80f6\u6c34\u8bed\u8a00\uff0c\u80fd\u591f\u628a\u7528\u5176\u4ed6\u8bed\u8a00\u5236\u4f5c\u7684\u5404\u79cd\u6a21\u5757(\u5c24\u5176\u662fC/C++)\u5f88\u8f7b\u677e\u5730\u8054\u7ed3\u5728\u4e00\u8d77\u3002\u5e38\u89c1\u7684\u4e00\u79cd\u5e94\u7528\u60c5\u5f62\u662f\uff0c\u4f7f\u7528Python\u5feb\u901f\u751f\u6210\u7a0b\u5e8f\u7684\u539f\u578b(\u6709\u65f6\u751a\u81f3\u662f\u7a0b\u5e8f\u7684\u6700\u7ec8\u754c\u9762)\uff0c\u7136\u540e\u5bf9\u5176\u4e2d\u6709\u7279\u522b\u8981\u6c42\u7684\u90e8\u5206\uff0c\u7528\u66f4\u5408\u9002\u7684\u8bed\u8a00\u6539\u5199\uff0c\u6bd4\u59823D\u6e38\u620f\u4e2d\u7684\u56fe\u5f62\u6e32\u67d3\u6a21\u5757\uff0c\u6027\u80fd\u8981\u6c42\u7279\u522b\u9ad8\uff0c\u5c31\u53ef\u4ee5\u7528C/C++\u91cd\u5199\uff0c\u800c\u540e\u5c01\u88c5\u4e3aPython\u53ef\u4ee5\u8c03\u7528\u7684\u6269\u5c55\u7c7b\u5e93\u3002\u9700\u8981\u6ce8\u610f\u7684\u662f\u5728\u60a8\u4f7f\u7528\u6269\u5c55\u7c7b\u5e93\u65f6\u53ef\u80fd\u9700\u8981\u8003\u8651\u5e73\u53f0\u95ee\u9898\uff0c\u67d0\u4e9b\u53ef\u80fd\u4e0d\u63d0\u4f9b\u8de8\u5e73\u53f0\u7684\u5b9e\u73b0\u3002
你这个iloc是pandas中的函数。
这个语句返回的是dataFrame从索引0到倒数第二行，步长为1的内容。
PYTHON的切片结束位置不包含偏移数本身，所以：-1切片到的最后内容是倒数第二位置的元素。
绛旓細new.iloc[:,[0,1]]浣跨敤鈥==鈥欑瓫閫-绛涙煡鈥滃磾鏃濈殑浜猴紙鍙兘绛涙煡鎸囧畾鏄庣‘鐨勶級new=file1.loc[(file1['鏀朵欢浜哄鍚']=='宕旀棴')|(file1['鏀朵欢浜哄鍚']=='宕旈湠')]print(new)浣跨敤loc鍑芥暟绛涢-str.contains鍑芥暟-绛涙煡鍚嶅瓧涓寘鍚'浜'鍜'娴'鐨勪汉 new=file1.loc[file1['鏀朵欢浜哄鍚'].str.contains...
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