Question

我正在尝试为DataFrame，

中某个列的行指定值

exchange_rates = {'TRY': 3.4155, 'NZD': 1.3683, 'HUF': 254.11, 'RUB': 57.185,
    'DKK': 6.1693, 'SEK': 7.9095, 'SGD': 1.337, 'CAD': 1.2087, 'JPY': 107.38,
    'AUD': 1.2339, 'HRK': 6.1621, 'CHF': 0.94569, 'ILS': 3.5163, 'THB': 33.1,
    'GBP': 0.75678, 'BGN': 1.6217, 'KRW': 1130.6, 'NOK': 7.7192, 'CZK': 21.641,
    'ZAR': 12.862, 'PHP': 50.809, 'MYR': 4.1945, 'EUR': 0.82919, 'MXN': 17.693,
    'CNY': 6.4615, 'HKD': 7.8076, 'RON': 3.8149, 'INR': 63.784, 'PLN': 3.5269,
    'IDR': 13163.0, 'BRL': 3.0892}

unique_currencies = ['CAD', 'CHF', 'CNY', 'EUR', 'JPY', 'GBP', 'SGD']

for cur in unique_currencies:
    cur_indices = df[df['currency'] == cur].index.tolist()
    for row_index in cur_indices:
        df.loc[row_index, 'common_amount'] = df.loc[row_index, 'amount'] / exchange_rates[cur]

因此，代码获取具有特定货币的行的索引，然后根据其汇率将值计算为“USD”到列common_amount。

我想知道最好的方法是什么？

更新

示例DataFrame，

   currency   amount
50      CAD   410.85
51      CAD   1441.68
17625   JPY   2797856.0
17663   JPY   1440.0
16734   CNY   27840.00
54546   CNY   273269.53
17654   GBP   384.0
17655   GBP   526.0
16732   CHF   474.7
16733   CHF   195173.3

Answer 1

我认为您需要按currency dict print (df['currency'].map(exchange_rates)) 50 1.20870 51 1.20870 17625 107.38000 17663 107.38000 16734 6.46150 54546 6.46150 17654 0.75678 17655 0.75678 16732 0.94569 16733 0.94569 Name: currency, dtype: float64 df['common_amount1'] = df['amount'].div(df['currency'].map(exchange_rates)) print (df) currency amount common_amount common_amount1 50 CAD 410.85 339.910648 339.910648 51 CAD 1441.68 1192.752544 1192.752544 17625 JPY 2797856.00 26055.652822 26055.652822 17663 JPY 1440.00 13.410318 13.410318 16734 CNY 27840.00 4308.597075 4308.597075 54546 CNY 273269.53 42291.964714 42291.964714 17654 GBP 384.00 507.412987 507.412987 17655 GBP 526.00 695.050081 695.050081 16732 CHF 474.70 501.961531 501.961531 16733 CHF 195173.30 206381.901046 206381.901046创建的div列除以if (edt1 == null){ edt1.setText(""); }：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:weightSum="1">

    <EditText
        android:id="@+id/first_number"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="2"
        android:layout_weight="0.40"/>

    <EditText
        android:id="@+id/second_number"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="2"
        android:layout_weight="0.40"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text=" = "
        android:layout_weight="0.10"/>

    <TextView
        android:id="@+id/result"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="4"
        android:layout_weight="0.20"/>

</LinearLayout>

pandas DataFrame将值分配给列的行

1 个答案: