Question

我以csv文件的形式获得了两组数据，这些文件具有23列和数千行数据。

14列中的数据对应于星系图像中恒星的位置。

问题在于，一组数据包含第二组数据中不存在的头寸值。它们都需要包含相同的位置，但是每个数据集的位置都偏离0.0002。

F435.csv的值比0.0002中的值大F550.csv。我正在尝试找到两个文件之间的匹配项，但是要在一定范围内，因为所有值都相差一定数量。

然后，我需要删除与不匹配值对应的所有数据行。

以下是两个文件中每个数据的样本：

F435W.csv：

NUMBER,FLUX_APER,FLUXERR_APER,MAG_APER,MAGERR_APER,FLUX_BEST,FLUXERR_BEST,MAG_BEST,MAGERR_BEST,BACKGROUND,X_IMAGE,Y_IMAGE,ALPHA_J2000,DELTA_J2000,X2_IMAGE,Y2_IMAGE,XY_IMAGE,A_IMAGE,B_IMAGE,THETA_IMAGE,ERRA_IMAGE,ERRB_IMAGE,ERRTHETA_IMAGE
1,2017.013,0.01242859,-8.2618,0,51434.12,0.3269918,-11.7781,0,0.01957931,1387.9406,541.916,49.9898514,41.5266996,8.81E+01,1.63E+03,1.44E+02,40.535,8.65,84.72,0.00061,0.00035,62.14
2,84.73392,0.01245409,-4.8201,0.0002,112.9723,0.04012135,-5.1324,0.0004,-0.002142646,150.306,146.7986,49.9942613,41.5444109,4.92E+00,5.60E+00,-2.02E-01,2.379,2.206,-74.69,0.00339,0.0029,88.88
3,215.1939,0.01242859,-5.8321,0.0001,262.2751,0.03840466,-6.0469,0.0002,-0.002961465,3248.686,52.8478,50.003155,41.5019044,4.77E+00,5.05E+00,-1.63E-01,2.263,2.166,-65.29,0.002,0.0019,-66.78
4,0.3796681,0.01240305,1.0515,0.0355,0.5823653,0.05487975,0.587,0.1023,-0.00425157,3760.344,11.113,50.0051049,41.4949256,1.93E+00,1.02E+00,-7.42E-02,1.393,1.007,-4.61,0.05461,0.03818,-6.68
5,0.9584663,0.01249223,0.0461,0.0142,1.043696,0.0175857,-0.0464,0.0183,-0.004156116,4013.2063,9.1225,50.0057256,41.4914444,1.12E+00,9.75E-01,1.09E-01,1.085,0.957,28.34,0.01934,0.01745,44.01

F550M.csv：

NUMBER,FLUX_APER,FLUXERR_APER,MAG_APER,MAGERR_APER,FLUX_BEST,FLUXERR_BEST,MAG_BEST,MAGERR_BEST,BACKGROUND,X_IMAGE,Y_IMAGE,ALPHA_J2000,DELTA_J2000,X2_IMAGE,Y2_IMAGE,XY_IMAGE,A_IMAGE,B_IMAGE,THETA_IMAGE,ERRA_IMAGE,ERRB_IMAGE,ERRTHETA_IMAGE,,FALSE
2,1921.566,0.01258874,-8.2091,0,37128.06,0.2618096,-11.4243,0,0.01455503,4617.5225,554.576,49.9887896,41.5264699,6.09E+01,8.09E+02,1.78E+01,28.459,7.779,88.63,0.00054,0.00036,77.04,,
3,1.055918,0.01256313,-0.0591,0.0129,9.834856,0.1109255,-2.4819,0.0122,-0.002955142,3936.4946,85.3255,49.9949149,41.5370016,3.98E+01,1.23E+01,1.54E+01,6.83,2.336,24.13,0.06362,0.01965,23.98,,
4,151.2355,0.01260153,-5.4491,0.0001,184.0693,0.03634057,-5.6625,0.0002,-0.002626019,3409.2642,76.9891,49.9931935,41.5442109,4.02E+00,4.35E+00,-1.47E-03,2.086,2.005,-89.75,0.00227,0.00198,66.61,,
5,0.3506025,0.01258874,1.138,0.039,0.3466277,0.01300407,1.1503,0.0407,-0.002441164,3351.9893,8.9147,49.9942299,41.5451727,4.97E-01,5.07E-01,7.21E-03,0.715,0.702,62.75,0.02,0.01989,82.88

下面是我到目前为止的代码，但是我不确定如何根据该特定列查找匹配项。我对Python还是很陌生，这个任务可能超出了我对Python的了解，但是我非常需要弄清楚它。我已经在这项任务上工作了数周，尝试了不同的方法。预先谢谢你！

import csv

with open('F435W.csv') as csvF435:
    readCSV = csv.reader(csvF435, delimiter=',')

with open('F550M.csv') as csvF550:
    readCSV = csv.reader(csvF550, delimiter=',')

for x in range (0,6348):
    a = csvF435[x]
    for y in range(0,6349):
        b = csvF550[y]

        if b < a + 0.0002 and b > a - 0.0002:
            newlist.append(b)
            break

Answer 1

您可以使用以下示例：

import csv

def isfloat(value):
  try:
    float(value)
    return True
  except ValueError:
    return False

interval = 0.0002

with open('F435W.csv') as csvF435:
 csvF435_in = csv.reader(csvF435, delimiter=',')
 #clean the file content before processing
 with open("merge.csv","w") as merge_out:
   pass
 with open("merge.csv", "a") as merge_out:
  #write the header of the output csv file
  for header in csvF435_in:
    merge_out.write(','.join(header)+'\n')
    break
  for l435 in csvF435_in:
    with open('F550M.csv') as csvF550:
      csvF550_in = csv.reader(csvF550, delimiter=',')
      for l550 in csvF550_in:
        if isfloat(l435[13]) and isfloat(l550[13]) and abs(float(l435[13])-float(l550[13])) < interval:
          merge_out.write(','.join(l435)+'\n')

F435W.csv：

NUMBER,FLUX_APER,FLUXERR_APER,MAG_APER,MAGERR_APER,FLUX_BEST,FLUXERR_BEST,MAG_BEST,MAGERR_BEST,BACKGROUND,X_IMAGE,Y_IMAGE,ALPHA_J2000,DELTA_J2000,X2_IMAGE,Y2_IMAGE,XY_IMAGE,A_IMAGE,B_IMAGE,THETA_IMAGE,ERRA_IMAGE,ERRB_IMAGE,ERRTHETA_IMAGE
1,2017.013,0.01242859,-8.2618,0,51434.12,0.3269918,-11.7781,0,0.01957931,1387.9406,541.916,49.9898514,41.5266996,8.81E+01,1.63E+03,1.44E+02,40.535,8.65,84.72,0.00061,0.00035,62.14
2,84.73392,0.01245409,-4.8201,0.0002,112.9723,0.04012135,-5.1324,0.0004,-0.002142646,150.306,146.7986,49.9942613,41.5444109,4.92E+00,5.60E+00,-2.02E-01,2.379,2.206,-74.69,0.00339,0.0029,88.88
3,215.1939,0.01242859,-5.8321,0.0001,262.2751,0.03840466,-6.0469,0.0002,-0.002961465,3248.686,52.8478,50.003155,41.5019044,4.77E+00,5.05E+00,-1.63E-01,2.263,2.166,-65.29,0.002,0.0019,-66.78
4,0.3796681,0.01240305,1.0515,0.0355,0.5823653,0.05487975,0.587,0.1023,-0.00425157,3760.344,11.113,50.0051049,41.4949256,1.93E+00,1.02E+00,-7.42E-02,1.393,1.007,-4.61,0.05461,0.03818,-6.68
5,0.9584663,0.01249223,0.0461,0.0142,1.043696,0.0175857,-0.0464,0.0183,-0.004156116,4013.2063,9.1225,50.0057256,41.4914444,1.12E+00,9.75E-01,1.09E-01,1.085,0.957,28.34,0.01934,0.01745,44.01

F550M.csv：

NUMBER,FLUX_APER,FLUXERR_APER,MAG_APER,MAGERR_APER,FLUX_BEST,FLUXERR_BEST,MAG_BEST,MAGERR_BEST,BACKGROUND,X_IMAGE,Y_IMAGE,ALPHA_J2000,DELTA_J2000,X2_IMAGE,Y2_IMAGE,XY_IMAGE,A_IMAGE,B_IMAGE,THETA_IMAGE,ERRA_IMAGE,ERRB_IMAGE,ERRTHETA_IMAGE,,FALSE
2,1921.566,0.01258874,-8.2091,0,37128.06,0.2618096,-11.4243,0,0.01455503,4617.5225,554.576,49.9887896,41.5264699,6.09E+01,8.09E+02,1.78E+01,28.459,7.779,88.63,0.00054,0.00036,77.04,,
3,1.055918,0.01256313,-0.0591,0.0129,9.834856,0.1109255,-2.4819,0.0122,-0.002955142,3936.4946,85.3255,49.9949149,41.5370016,3.98E+01,1.23E+01,1.54E+01,6.83,2.336,24.13,0.06362,0.01965,23.98,,
4,151.2355,0.01260153,-5.4491,0.0001,184.0693,0.03634057,-5.6625,0.0002,-0.002626019,3409.2642,76.9891,49.9931935,41.5442109,4.02E+00,4.35E+00,-1.47E-03,2.086,2.005,-89.75,0.00227,0.00198,66.61,,
5,0.3506025,0.01258874,1.138,0.039,0.3466277,0.01300407,1.1503,0.0407,-0.002441164,3351.9893,8.9147,49.9942299,41.5451727,4.97E-01,5.07E-01,7.21E-03,0.715,0.702,62.75,0.02,0.01989,82.88

merge.csv：

NUMBER,FLUX_APER,FLUXERR_APER,MAG_APER,MAGERR_APER,FLUX_BEST,FLUXERR_BEST,MAG_BEST,MAGERR_BEST,BACKGROUND,X_IMAGE,Y_IMAGE,ALPHA_J2000,DELTA_J2000,X2_IMAGE,Y2_IMAGE,XY_IMAGE,A_IMAGE,B_IMAGE,THETA_IMAGE,ERRA_IMAGE,ERRB_IMAGE,ERRTHETA_IMAGE
2,84.73392,0.01245409,-4.8201,0.0002,112.9723,0.04012135,-5.1324,0.0004,-0.002142646,150.306,146.7986,49.9942613,41.5444109,4.92E+00,5.60E+00,-2.02E-01,2.379,2.206,-74.69,0.00339,0.0029,88.88

Python：删除在范围内不匹配的所有csv文件行

1 个答案: