当尝试使用 as.numeric 将一列字符（数字字符串，例如“0.1234”）转换为数字时，某些值会返回NA警告“强制转换引入的 NA”。作为 s 返回的字符NA似乎与正确作为数字返回的字符没有任何不同。有谁知道可能是什么问题？
已经尝试查找任何可以隐藏在某些值中的非数字字符（如 \',\'）。我确实找到了包含“-”（例如“-0.123”）的字符串确实变成了NAs，但这些只是变成了NAs的字符串的一部分。另外，尝试寻找字符串内的空格。这似乎也不是问题。
data$y\n [1] "0.833250539" "0.820323535" "0.462284612" "0.792943985" "0.860587952" "0.729665177" "0.461503956" "0.625871118" \n [9] "0.740999346" "0.962727964" "0.971089266" "0.869004848" "0.828651766" "0.900648732" "0.970326033" "0.898123286" \n[17] "0.911640765" "0.902442126" "0.843392097" "0.763421844" "0.892426243" "0.380433624" "0.925017633" "0.725470821" \n[25] "0.699924767" "0.689061225" "0.907462936" "0.888064239" "0.913547115" "-\xe2\x80\xac0.625103904\xe2\x80\xad" "0.897385961" "0.889727462" \n[33] "0.90127339" "0.947012474" "0.948883588" "0.845845512" "0.97866966" "0.796247738" "0.864627056" "0.266656189\xe2\x80\xad" \n[41] "0.894915463" "0.969690678" "0.771365656\xe2\x80\xad" "0.88304436" "0.954039006" "0.836952199" "0.731558669\xe2\x80\xad" "0.907224294" \n[49] "0.622059127" "0.887742343" "0.917550343" "0.97240334\xe2\x80\xad" "0.902841957" …