Regex R字符串操作
我正在使用“readLines”命令生成的字符向量 在这个向量的某一部分,我有以下几点:Regex R字符串操作,regex,r,string,gsub,Regex,R,String,Gsub,我正在使用“readLines”命令生成的字符向量 在这个向量的某一部分,我有以下几点: > metadata[147:157] [1] " RADIANCE_MULT_BAND_1 = 1.2852E-02" " RADIANCE_MULT_BAND_2 = 1.3161E-02" [3] " RADIANCE_MULT_BAND_3 = 1.2128E-02" " RADIANCE_MULT_BAND_4 = 1.0227E-02" [5] "
> metadata[147:157]
[1] " RADIANCE_MULT_BAND_1 = 1.2852E-02" " RADIANCE_MULT_BAND_2 = 1.3161E-02"
[3] " RADIANCE_MULT_BAND_3 = 1.2128E-02" " RADIANCE_MULT_BAND_4 = 1.0227E-02"
[5] " RADIANCE_MULT_BAND_5 = 6.2583E-03" " RADIANCE_MULT_BAND_6 = 1.5564E-03"
[7] " RADIANCE_MULT_BAND_7 = 5.2458E-04" " RADIANCE_MULT_BAND_8 = 1.1574E-02"
[9] " RADIANCE_MULT_BAND_9 = 2.4459E-03" " RADIANCE_MULT_BAND_10 = 3.3420E-04"
[11] " RADIANCE_MULT_BAND_11 = 3.3420E-04"
我需要的是只得到每一行的值,或者更好的,在相等符号之后的所有值。大概是这样的:
factor <- as.numeric (everything coming after the equal symbol (metadata[147:157]))
factor您可以尝试regex
as.numeric(sub(".*= ?", "", metadata))
#[1] 0.01285200 0.01316100 0.01212800 0.01022700 0.00625830 0.00155640
#[7] 0.00052458 0.01157400 0.00244590 0.00033420 0.00033420
数据
元数据谢谢@akrun。这真的奏效了。我无法想象会那么容易。。。
metadata <- c(" RADIANCE_MULT_BAND_1 = 1.2852E-02",
" RADIANCE_MULT_BAND_2 = 1.3161E-02",
" RADIANCE_MULT_BAND_3 = 1.2128E-02",
" RADIANCE_MULT_BAND_4 = 1.0227E-02",
" RADIANCE_MULT_BAND_5 = 6.2583E-03",
" RADIANCE_MULT_BAND_6 = 1.5564E-03",
" RADIANCE_MULT_BAND_7 = 5.2458E-04",
" RADIANCE_MULT_BAND_8 = 1.1574E-02",
" RADIANCE_MULT_BAND_9 = 2.4459E-03",
" RADIANCE_MULT_BAND_10 = 3.3420E-04",
" RADIANCE_MULT_BAND_11 = 3.3420E-04")