Question

我有一个这样的数据框：

    @Test
    public void testguardarMensaje() throws IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException, SecurityException, InstantiationException{

        String datoTest = "1=123456";   

        Constructor<PsPort> constructor = PsPort.class.getDeclaredConstructor(new Class[] {String.class});
        constructor.setAccessible(true);
        PsPort port = constructor.newInstance("middleware.conf");

        PsPort drMock;

        int hash1 = datoTest.hashCode();
        String hashString1 = String.valueOf(hash1);
        String combinedIdDataHashString1 = datoTest +"="+ hashString1;

        drMock = strictMock(PsPort.class);
        byte[] datoByte = port.encriptarDesencriptarMensaje(combinedIdDataHashString1.getBytes(), Cipher.ENCRYPT_MODE);
        drMock.guardarDato(datoByte);
        replayAll();

        int hash = datoTest.hashCode();
        String hashString = String.valueOf(hash);
        String combinedIdDataHashString = datoTest +"="+ hashString;

        byte[] datoByte2 = port.encriptarDesencriptarMensaje(combinedIdDataHashString.getBytes(), Cipher.ENCRYPT_MODE);

        DatagramPacket paquete = new DatagramPacket(datoByte2,datoByte2.length);
        paquete.getData();

        DataReader dr = new DataReader(port, null, 100, "=", "C:/Users/Asier/Desktop/logs/");

        dr.guardarMensaje(paquete, port);
        verifyAll();        
    }

我想获得一个包含所有具有相同值的ID的新表，如下所示：

ID  Value
1   C
2   B
3   B
4   A
5   C
6   B
7   B
8   A
9   C
10  B
11  B
12  A
13  C
14  B
15  B

我不介意昏迷是否分开。

由于

Answer 1

对于每个独特的“价值”，我们可以使用aggregate到paste'ID'

aggregate(ID~Value, df1, FUN= toString)
# Value                         ID
#1     A                   4, 8, 12
#2     B 2, 3, 6, 7, 10, 11, 14, 15
#3     C                1, 5, 9, 13

如果我们需要list列，请使用c作为FUN

aggregate(ID~Value, df1, FUN = c)

使用其他软件包（例如data.table

）也可以这样做

library(data.table)
setDT(df1)[, .(Values =toString(Value)), by = ID]

或dplyr

library(dplyr)
df1 %>%
    group_by(ID) %>%
    summarise(Values = toString(Value))

获取数据框中具有相同值的所有ID

1 个答案: